I've used some free online services to set up a campaign website and a message board.
The website is just a place where I have noted house rules, posted maps, brief histories and bits of world information etc. - however, it probably doesn't get used all that much ...but it is there nonetheless for players to check out from time to time. I've tried to give it a 3E 'look' and also tried to break the text up with little sketches and pic's in an attempt to make it look less daunting to new players and maybe even a little easier one the eye (well that was the plan anyway

).
Olaf the Stout said:
P.S If you do have a campaign website, feel free to share it with us!
Here's the link to the site (I think I've probably posted it before in an older topic):
http://airtha.freehostia.com
The main thing I like about the webspace provider is that although it's free it doesn't have any annoying adverts (either at the top of the pages or as pop-ups). It does however have a file size limit of 500KB, 250MB total storage, and 5GB monthly bandwidth (which is plenty for me).
The message board I've set up is quite a simple affair - but that gets used a lot more. We use it to post a brief summary of every session, keep track of XP, discuss possible house rules, keep track of party objectives, etc. (in much the same way as some of the folks above).
All in all we could probably manage without them... but I kinda like having them around
