Meet and tweet for a good cause at Twestival

Volunteers from over 175 cities around the globe are organizing Twitter festivals, or "twestivals" to help the charity water cause. Also, Twitter users will have a chance to meet face-to-face instead of just over the interwebs.

The cost of your Twestival ticket will feed 40 people clean water for a whole year. Donate here.

The local San Francisco venue is the Paradise Lounge, and there should be a lot of entertainment. The events worldwide have attracted many global partners including Virgin Media, Live Earth, Mashable and Amiando.

There will be live broadcasts from San Francisco and 5 other major cities including London, Paris, New York, and Austin.