I know we are not allowed to add direct URL's on this board, so will not provide a direct link. However, if you search on google for: "gossamer threads forum" the first two results will get you to who I recommend.
I like this forum for a couple reasons. One, you can buy it outright, and it is yours.... no yearly maintenence fees. Two, it is VERY configurable. Three, they have a VERY active forum of members who will help you get it running just like you want. And fourth, the people who make this are VERY helpful in getting you set up (and again, no extra fees!) I use this forum package, mainly because my site also uses another of their products, and I wanted to integrate the two (one log in for both sites). It also has support for plug-ins, so you do not need to "hack code" to customize (and re-hack for every upgrade!). If you want to see it in action on my site, PM me and I will send a URL.
The down sides... you do need MySQL. Also, to really run it fast, you need mod_Perl. Neither should be much of a problem if you have your own servers. Also, I would note that this is a fairly new forum, and it does not yet have all the bells and whistles of some of the more established forums. But I do know they are working on a version two, which will substancially enhance the usibility of the software. Based on my experience with their other software packages, it should be an easy upgrade for you.
If you are interested, I would also suggest looking at their support forum (also on their site) for the GT Forum software. You will get a good overview of what any existing limitations are, and how people help each other out in configuring the forum software.
Again, I cannot say enough for the support, both from users and the company that makes it.
(I am a user of this software, and in no way affiliated with the makers, other than I REALLY like them!)
[edited by: carfac at 4:38 pm (utc) on Mar. 3, 2003]