Have you ever set up a wiki for your ongoing campaign? Do you have trouble remembering what happened months, years ago?  Did Bob kill the evil necromancers uncle or was it just uncle's cousin's college roomate?

For my ongoing 4e Eberron game, The Ancient Pact, I started using http://www.obsidianportal.com/  I like it, its pretty simplistic, which in this case is pretty good, because all I need is a wiki with some support for inviting players into the game.

You can see how I'm using it, here: http://www.obsidianportal.com/campaigns/ancientpact   But if you look around, you can see many other people using it much more thoroughly than I am.