Mogi, Item Hunt is a GPS game based in Japan that people play through their cellphones and hunt for treasure (gifts, flowers, etc) on a virtual map of Tokyo based on their location. It integrates IM by letting players give hints to others as they see their icons run around on the map. I like how its very 2D and doesnt try to hype up the interface over trying to make it look too real. I guess thats a limitation of having it all run on a cellphone, which is good and minimal. I wonder how many players hit lamp posts when they are trying to walk and IM at the same time?