Apple Insider discovered a patent filing for what appears to be the rumored iWatch. The filing is for a "bi-stable spring with flexible display" that "allows the accessory device to be easily worn in a number of convenient locations." Unlike previous rumors suggesting that the watch ran an operating system all its own, this new evidence paints the gadget as something that will connect to an external device — like an iPhone — over a wireless protocol like Bluetooth.

The display isn't confined to a square or circular watch face. Rather, the iWatch's screen runs lengthwise down the entirety of the bracelet. The device appears to use built-in accelerometers and gyroscopes to orient displayed data — say, the time — in the general direction of the user's eyeballs, no matter where your arm is relative to their head.

But the most interesting revelation from the patent filing might be how you put the thing on. Here's what the patent, which was filed in August 2011, says about the spring mechanism:

Bi-stable springs have two equilibrium positions. This allows a device with a bi-stable spring to assume two distinct configurations. The most recent widespread use of such a device was the slap bracelet, also called the slap wrap. The slap bracelet consists of layered flexible steel bands sealed within a fabric cover. Typical slap bracelets are roughly one inch in width by nine inches in length. In a first equilibrium position they can be flat. The second equilibrium is typically reached by slapping the flat embodiment across the wrist, at which point the bracelet curls around the wrist and stays relatively secure in a roughly circular position. [United States Patent and Trademark Office]

So... Apple's rumored iWatch might be a slap bracelet. Earlier today, it was reported that Google has tapped the style geniuses at Warby Parker for help designing its glasses. In other words, the future of wearable computing, ladies and gentlemen, is starting to look like a bad caricature of Williamsburg circa 2010.