I'm trying to set up a forum for a college writing club. There are about 10 gazillion options. Assuming zero funding.... what do? proboards seems ok, but I'm a little worried by the fact you MUST specify m/f gender to even make a forum. (Even having that question on there creeps me out.) The rest are hard to judge because their homepages look a couple years old.
Most of the free forum sites don't update their homepages, although they do update their software. Their applications all tend to be "stock" from the 1980s - asking for info they don't even care about nor can verify. I ran a forum for a while based on a neverwinternights server I ran and used 100% false information since in my business while being a geek is expected it's also frowned on by HR departments.