Now this sounds interesting. Yahoo! oneConnect is a way of keeping in touch with people via your mobile phone, combining IM, email,phone numbers and text.
It's also integrated with a number of social networks, including Bebo, MySpace, Facebook, Twitter and Last.fm.
And you can see where people are, so if you're on a night out but you're really not having a good time, you can see if a friend is at a nearby bar so you can go and join them.
This is the kind of thing more developers should be making for mobiles (unfortunately Yahoo! don't seem to support my phone with Yahoo! Go at present so I can't use that, and probably won't be able to use this). I'll be watching this carefully...