This is from the Tropical Fish forum. Someone was tired of having 2 tanks to maintain, so added the betta to the community tank. However the flow from the filter was too strong for the betta, and the slow eating betta wasn't getting much food with the other fish eating so fast.

This idea is working well.

http://www.flickr.com/photos/gvilleguy/12794550275/

I think it is a fascinating idea!