Back in 2007 I started working at a startup named Groovr (which appears to not be in operation anymore.)
The idea behind Groovr was sort of an enhanced Twitter, only without the message limitation. It natively supported image and movie messages being sent to the service. A lot of people loved these features but my favorite was something completely different.
We had been using an idea back then that is all the rage today. "Check Ins" - that is, checking into a location so you're friends can see where you currently are. It was as easy as sending a quick message to Groovr to find which of your friends are checked in nearby or who has previously checked into the place you were currently checked into.
We even had iJustine fly out for a few days and we all were part of her live life cast that she was doing at the time.
Services like FourSquare, GoWalla, and Loopt offer this now and have it nailed down pretty well. Even turned it into a social game type of system that makes it super addicting to use and keeps the users coming back for more.
Granted we had a lot of problems with the system and it was very "cavemanish" compared to the services today that offer a similar experience. Remember though, at that time no one else was doing this (as far as I knew anyways.) Still, Groovr had a very hip feel and our user base, though small, loved the service and the community within it.
Not sure why I decided to write this post but I tried to go to the Groovr website for the first time in a year and it seems to not be running anymore. Sort of sad and sent me down memory lane. Oh well, on to the next one... RIP Groovr.
Anyway, Check In's may be going the way of the Dodo if Mark Cuban has his way.