The town of Riverhead, Long Island, announced last week that it had found a new way to raise revenue — by using Google Earth to find undeclared backyard pools so the city could tax the homeowners. This "enterprising Google Earth scouring" has apparently netted the town $75,000 in licensing fees. But this isn't the first time the software has been used by law enforcement to catch criminals, nor even the first time it has been used to find illegal pools. From pot growing to boat dumping, a list of five legal cases cracked by Google's innovative satellite mapping website:

1. Secret swimming in Greece
Until recently, the Greek government was aware of only 300 swimming pools in the wealthy suburbs of Athens. But in the wake of the country's recent financial meltdown, a newly created enforcement agency began using Google Earth to peek into backyards — and found that the real number was close to 17,000. The site also revealed many undeclared vacation villas and home extensions. "Maybe if the Greek government had been a little more tech savvy the past six years, they wouldn't be in such a mess?" notes Seth Weintraub at Fortune.

2. Pot growing in Wisconsin
When police officers in Racine, Wis., arrested Dean Brown for possession of 18 pounds of marijuana in 2007, they also found a GPS unit around his neck that held coordinates to all his other marijuana plants in the area. Officers plugged the coordinates into Google Earth and immediately discovered the plants."Dude," says Ryan Singel at Wired. "If you can’t remember where your own stashes are, you should think of that as a sign."

3. Cutting down the Brazilian rain forest
The Surui Indian tribe in Brazil teamed up with Google Earth in 2007 to keep loggers and miners out of the tribe's 6,000-acre Amazon reservation. Deforestation in the area has since decreased to the lowest figures in decades. "We feel an obligation to help groups like this when it is so clear that our tools can make an important positive impact," said Google spokeswoman Megan Quinn.

4. Evading taxes in Italy
An Italian businessman told Italy's Guardia di Finanza — their equivalent of the IRS — that he sold a villa in Sardinia last year for 280,000 euros ($367,000). Suspecting fraud, the Guardia looked it up on Google Earth and realized the actual value of the villa would have been far higher, given its size and prominent waterfront location. In the end, the unlucky fraudster was found to owe 7 million euros ($9.2 million) in back taxes. The taxmen identified the villa from one distinctive detail, says Italy magazine: Its "phallic-shaped swimming pool."

5. Dumping trash in Florida
After a sheriff's deputy found an abandoned boat about 15 miles south of Pensacola, Fla., he consulted satellite pictures taken earlier by Google Earth to see if he could spot the vessel in a nearby berth. He quickly found it moored at Dwight Foster's dock, and promptly arrested him for illegally dumping the boat — a crime that carries a $5,000 fine and five-year jail term. It would have cost Foster $18 to properly dispose of it, notes Edecio Martinez at CBS News.