I've removed Darkboard from this site. It's too old, too basic, and I don't think I should encourage its use by leaving it available. I wrote it years ago as a fun project for learning Perl. I don't have the time or interest to rewrite it properly, so it's better dropped.
You might take a look at YaBB, Yet another Bulletin Board. It's Open Source, and I've heard good things about it. I haven't actually tried it myself. I don't care for web bulletin boards; I prefer Usenet. (If you want a good freeware Usenet client for Windows, take a look at Xnews.)
If you're really interested in seeing this amateur program you can email me at darkboard@dwall.fastmail.fm (David Wall). I can always send interested persons a copy, but with the caveat that I really don't think you should use it for anything serious.
If you can see this, chances are your browser is old, maybe Netscape 4? If you can possibly do so, please upgrade so web designers can have an easier life. Newer browsers that support CSS <http://www.w3.org/Style/CSS/> should not see this paragraph.