I’m still having the same problem Loopydude described: when I click the “Message Boards” link on the Straight Dope home page, my browser downloads a file called “sdmb” to my desktop.
When I click on the “Threadspotting” link, it goes to the thread, and I can navigate from there.
Mac OSX version 10.3.7 (just upgraded today, but the problem began yesterday)
Safari version 1.2.4
10:00 am 12/23/04
Oddly, the problems are back. I swear. I didn’t change anything, I just tried to click on IMHO just now, and downloaded “forumdisplay.php” again. Weird. 
Or an overdose of Christmas spirit and boozy parties
Started yesterday at approx 17:00 GMT.
I get the message as I described on my work machine. Running Firefox 1 and IE6 on XP SP1 and both give the same. It started when I was reading the boards and tried to open a pit thread(can’t remember which one)
It works with my laptop though with the same browsers
I saw the same problem with Mozilla 1.4. Since this is a version customized for my company, I assumed it was just me - perhaps not.
It only affected the Pit for me for some weird reason. It’s been fine all of today.
If we can get enough error messages, maybe we can reverse engineer the code. 
I can now get into IMHO AND search! Woo-hoo! Thanks Hamsters! 