1. Going to a very formal Christmas party where you won't be carrying a fancy evening purse because it interferes with all the free booze. You gotta use both hands in this case, and you'll need a phone to find your way back home.
2. It's Halloween, and you're dressed up like a slutty tech agent.
3. You use it to hold a recorder, that can only record some very incriminating conversations. Especially if you're planning to blackmail a very bad man.
Otherwise, you're on your own girlfriend. Let us know if you get some undesirable looks, and don't say we didn't tell you so. Via Ubergizmo