[theantidote]

A Taxi service site and iPhone app. Lets you send your current location to the cab company with your iPhone and then track the cab as it arrives. Maybe even offer a prepay option so you can pay with your paypal account and just read off a confirmation number to the cab driver or something at the end of the trip for them to bill you with. Maybe in order to prevent confusion over more than one cab being called from the same location the app can light your phone screen up in a unique color for you to call the cab with as it approaches.

This wouldn't really be necessary in NYC where cabs are ubiquitous but in DC it would be useful.

EDIT: Crud, already sorta exists: http://taximagic.com/

[bemmu]

Why are you disappointed that it exists? My reaction is more like "great, that problem is solved, now I can make something else".

[theantidote]

I just thought I was original but it turned out I wasn't.