Here's a neat idea that we'd like to see take off: tubePing.
tubePing.com is the only website online whose SOLE purpose is to assist London's tube and rail community contact that certain somebody that they may have seen whilst on their journey. With 976 million passengers carried on the tube each year it's hardly surprising that many of us make some kind of connection with a fellow tube or rail passenger but are always in too much of a rush or perhaps a little shy to do anything about it!
Other cities probably have people who actually speak to one another, but here in Blighty we NEED this kind of service. It also promises to save us a fortune in the lost Moo cards that we are constantly trying to drop in handbags, pockets and purses when no one is looking...
Also it could be the only good thing to ever come out of Sliding Doors.
Early days yet, but use it if you get the chance and we'll see if it grows.