check out schamps. Sounds like a alcohol drink but is integration of Google maps and twitter

What is Taweet?

Taweet (beta) is a free Twitter application and social calendar that allows people and businesses to streamline promotional scheduling for events, product launches, lifecasting and more! Unlike Twitter scheduling applications you may have seen before, Taweet is focused on promoting the topics of your Future Tweets (FT) up until they occur to create buzz or to share with friends.

Round up live meeting point en do stuf with your friends.
and is a initiative of GixOO Studios,