Low-grade methane leaks are bad for business (that gas could be heating up a home) and bad for the environment (it traps heat up in the atmosphere). Because a methane spill is invisible and has no smell — unless there's about to be an explosion (and if so, run!) — it can be hard to track one down.

That's where a tricked-out Google Street View car comes into play. Google Earth Outreach and the Environmental Defense Fund have teamed up to turn several Subaru Imprezas into mobile methane trackers. As Bloomberg reports, scientists add tubing across the front grill, which helps push a constant stream through a very small dehumidifier and then into a gas analyzer. Real-time data is streamed to a monitor, showing how fast the car is driving and the amount of methane on the street.

The pilot project's results were released on Wednesday, with information coming in from Boston, Indianapolis, and Staten Island. The findings seem to show that older cities have more of an issue with leaks, likely due to old infrastructures. Indianapolis, which has newer pipes, was the cleanest, with just one leak recorded for every 200 miles.

Those involved in the project are excited to use the information as a way of influencing how cities plan in the future. "This is the beginning of what I really see as a big shift in the way we can give people data about the environments they live in," Steven Hamburg, chief scientist for the EDF, told Bloomberg.

For in-depth maps of methane leaks in the three areas, visit the Environmental Defense Fund website.

Fans of The Walking Dead who have always wanted to own part of a town and happen to have $680,000 are in luck: Downtown Grantville, Georgia, featured on an episode during the show's third season, is up for sale on eBay.

The town's former mayor, Jim Sells, owns the historic property and is hoping to sell it to someone who has "a vision," he told BuzzFeed. He said he'd like to see it "active and thriving," and noted that fans of The Walking Dead flock to the town on tours. The property boasts nine buildings with apartments, restaurants, office space, a pharmacy, and retail space, and is located 40 miles away from Atlanta. Its moment in the spotlight isn't done yet, either — three movies, including a sequel to The Ring, will soon be filmed in the area. —Catherine Garcia

Police stations across the United States are now doubling as safe havens for Craigslist buyers and sellers.

In Naperville, Illinois, police Cmdr. Ken Parcel said Monday that allowing Craigslist users to buy and sell in the station lobby is "a preventative measure to ensure there's a safe place to allow [buyers and sellers] to conduct their normal lives and businesses." He stressed that officers and staff are not assisting with transactions. Chicago does not have official safety zones, but the city's police department did say in a statement it urged people who are buying and selling to meet in well-lit public places and bring along a friend or relative.

In Indiana, a number of violent crimes linked to Craigslist made the town manager of Whitestown spring to action. Dax Morton told the Chicago Tribune the violence was the "straw that broke the camel's back," and that residents in his town can now use the municipal complex for transactions and can ask for police supervision. "My wife uses Craigslist a lot," he said. "I think it's a great idea."

During her four years as secretary of state, Hillary Clinton didn't have a government email account and used only her private account, in possible violation of the Federal Records Act, The New York Times reported Monday night. Just two months ago, Clinton advisers reviewed tens out thousands of pages of Clinton's emails from that period and turned 55,000 pages over to the State Department for archiving.

This blockbuster report didn't escape the notice of former Gov. Jeb Bush (R), who made public 250,000 emails from his eight years as governor back in December, before an anticipated 2016 presidential run:

"Hillary Clinton should release her emails," Bush spokeswoman Kristy Campbell told the Tampa Bay Times. "Gov. Bush believes transparency is a critical part of public service and of governing." And she, too, pointed to jebemails.com. But "the Bush files, though enormous, are not complete," noted the Miami Herald's Mary Ellen Klas in January:

The former governor conducted all his communication on his private Jeb@jeb.org account and turned over the hand-selected batch to the state archives when he left office. Absent from the stash are emails the governor deemed not relevant to the public record: those relating to politics, fundraising, and personal matters while he was governor. [Tampa Bay Times]

In case you weren't counting, the Iowa caucuses are in 11 short months.

File this under "not smart": A Nebraska man was cited for possession of less than an ounce of marijuana after deputies found a sour cream container marked "Not Weed" in his car that was actually filled with the stuff.

The 21-year-old Lincoln man was stopped on Saturday night, and despite his best efforts, Lancaster County Sheriff's deputies weren't fooled by his fake label and opened up the container to discover 11.4 grams of marijuana, the Lincoln Journal Star reports. The man admitted it was his, and was arrested for driving under the influence of alcohol. Points for at least trying to pull a fast one?

On Monday, United Airlines announced it will stop accepting bulk shipments of rechargeable batteries amid safety concerns.

The batteries are often shipped by the tens of thousands in one cargo container on a plane, and tests by the Federal Aviation Administration over the past year have shown that just one battery overheating can transfer to others, causing a chain reaction of batteries releasing explosive gases. Several tests have ended with fiery explosions, The Associated Press reports.

Delta Air Lines stopped accepting bulk shipments on Feb. 1, but both Delta and United will still allow bulk shipments on board if the batteries are inside of something else, like a laptop, as the belief is that gives the battery a buffer. In a statement, United said, "Our primary concerns when transporting dangerous goods are the safety of our customers, our customers' shipments, and the environment."

If you have a favorite duet from the last 50 years, there's a good chance Jimmy Fallon and Kelly Clarkson perform it in their "history of duets" on Monday night's Tonight Show. Everyone from Human League to Sonny and Cher get sing-outs, plus some musical collaborations you might have forgotten about (yes, we're talking about you, Paula Abdul and MC Skat Kat). And finally, we learn a vocal impression Fallon can't do: His Aaron Neville is terrible. Otherwise, grab a seat and enjoy the show. It's a good one. —Peter Weber

If Utah passes a medical marijuana bill, a DEA agent warns, more than just the patients might get stoned.

During testimony to a Utah Senate panel last week, DEA special agent Matt Fairbanks said that wildlife could "cultivate a taste" for the plant, The Washington Post reports. "I deal in facts," said Fairbanks, a member of the DEA marijuana eradication team in the state, talking about his experience with pot growing on public lands. "I deal in science. Personally, I have seen entire mountainsides subjected to pesticides, harmful chemicals, deforestation, and erosion. The ramifications to the flora, the animal life, the contaminated water, are still unknown."

Fairbanks said he witnessed at some illegal marijuana grow sites rabbits who became dependent on marijuana and "refused to leave us... his natural instincts to run were somehow gone." As the Post points out, if it becomes legal, the plant won't be growing out in the wild, so bunnies would be able to frolic through the forest drug-free. The panel approved the bill, and it will be debated in the full Senate this week.

During her four years as secretary of state, Hillary Clinton used her personal email account exclusively and did not have a government email address, The New York Times reports.

This may have violated the Federal Records Act, which requires that personal emails be preserved on department servers; letters and email written by federal officials are supposed to be retained and filed so congressional committees, media outlets, and historians can easily find them, with some exceptions for classified and sensitive material. To comply with new federal record-keeping practices, Clinton's advisers gave 55,000 pages of emails to the State Department two months ago, and a spokesman said she is adhering to the "letter and spirit of the rules."

Jason R. Baron, a lawyer at Drinker Biddle and Reath and former director of litigation at the National Archives and Records Administration, said there really wasn't a reason why Clinton should have been using just her personal email address throughout her tenure. "It is very difficult to conceive of a scenario — short of nuclear winter — where an agency would be justified in allowing its cabinet-level-head officer to solely use a private email communications channel for the conduct of government business," he said.

Now that Costco's deal with American Express is over, Citigroup Inc. will start issuing the company's credit cards and Visa Inc. will be the credit-card network beginning in 2016.

For the last 15 years, American Express was the only card accepted at Costco, and the partnership, which ended last month, represented 8 percent, or $80 billion, of the credit card company's billed business and 20 percent, or $14 billion, of its interest-bearing credit portfolio, the Los Angeles Times reports.

On April 1, 2016, transactions will be processed by Visa and Citi will be the exclusive issuer of co-branded credit cards, with the company also accepting debit cards, cash, and other Visa cards as forms of payment. The company said in a statement that the deal is still subject to the purchase of Costco's existing co-branded credit card portfolio by Citi, but they expect it to be sold.

The wife of Raif Badawi, the Saudi Arabian blogger currently serving 10 years in prison and facing 1,000 lashes after criticizing clerics on his site, says that her husband could soon face the death penalty on apostasy charges.

Ensaf Haidar told The Independent official sources inside Saudi Arabia told her that criminal court judges want to try him for apostasy, even though charges were thrown out in 2013 after Badawi told the court he was Muslim; the evidence against him was the fact that he "liked" a Facebook page for Arab Christians. His family had been hoping that international condemnation against his sentence would pressure Saudi Arabia to release him from prison. Badawi has been flogged once, and subsequent punishments have been postponed, The Independent reports.