This is all well and good, until a pedestrian rips your iPad out of the plastic pocket, jumps on their flame-throwing moped and speeds off, leaving you bereft and without visible turning aids.
Maya Design is behind the Sprocket Pocket, with the pattern download up on their site if you want to take a stab at making yourself - otherwise, they'll be selling the "rugged sewn industrial nylon patch with integrated zipper and protective screen overlay" once their beta testing is finalised. The app itself isn't available yet though, but once they start offering it you'll just have to crank up the brightness setting to maximum and turn off the auto-brightness switch.
Because the iPad has an accelerometer, if you turn your body the way you're about to turn, the iPad will sense the next direction and then display the action for anyone lucky enough to be behind you. Just like indicators! Only... more expensive. [Maya via Wired]