App where people rank and post excerpts of books. The best part: you can scan the bar code on a library and now better the book you'll buy.
Social network that help find lost pets. You do check in where you lost your pet or where you saw a pet lost, with a picture of him.
The same logic from 4square but instead of check in on places, you do check out in parking lots. This way you know where is free to park.
One web store where people get new stuff by trading old stuff with other people. It's all about people and stuffs. NO money allowed. #bhjam
50% discount on drinks for people who go to fast food or coffee shops bringing their own mug/cup. #bhjam
Working law that allow people to use part of their retiring time as a sabbatical time. This would only increase our working productivity.
You enter the site and choose: vocal, guitar, drums, etc. Then enter in a room (live studio) and make a jam session with whoever is there.