Blursoft Metaforum - Free

Here is a nice tool that allows you to create your own free forum. Its free and very functional, allthough not very customizable. But its free... and... free... Good if you are on a tight budget.

See these examples :
http://www.planetblur.org/hosted/txrcrca/
http://www.planetblur.org/hosted/issyp/

http://www.blursoft.com/metaForum/