The Purse Phone uses Caller ID lights to signal calls

We don't claim to know a lot about handbags, but we do know a little bit about cellphones, and we know that under certain common circumstances — like when you're in a way-too-loud club — that carefully selected ringtone is going to go completely unnoticed. So the Phone Purse, a product concept created by Kerry Bodine, seems like a great solution
(for the handbag-toting half of the population, that is). It's a bag with integrated lights that are triggered by cellphone calls, and flash in a pattern based on the caller's ID. Of course, if you're someplace where it's too loud to hear the phone ringing, chances are it's also too loud to pick up a call, but at least you'll know which calls you've missed, and whether it's worth your while to excuse yourself to return them, or you can safely ignore them until much,
much later.

[Via textually.org]