Several years back (about 2002), a private group of mobile enthusiasts that I am involved with, talked about what the next killer app will be. One of the things that came up was a location-based messaging service we termed that time as hypermessaging.

Basically, think of Jaiku or Twitter now, but each message is geo-tagged. There is so much potential in such an app -- finding friends, querying what's up in the area, finding the best deals, finding items for sale in the area, leaving virtual notes to someone, tracking services, etc, etc -- so much potential.

More importantly, this kind of service create communities (mind you, social networking wasn't even popular 5 years ago when we were discussing this killer app). Howard Rheingold, author of Smart Mobs, gave us an insight on how (virtual) communities are created. Think New York -- China Town, Little Italy, SoHo, etc. -- how did those communities start? What triggered their decisions to stay at that part of Manhattan?

Well I digress, but notice how new devices that are coming out now have built-in GPSes. 'Where am I?' or 'Where are you?' when put into a much bigger context, can be so much encompassing.

No wonder Google bought Jaiku.