Spam Motel is great. It's a very small .exe file that I have on my desktop. I gave it a keyboard shorcut, so whenever I need a new e-mail address, I hit 3 keys and it pops up. I select my account, give it a name, and click a button. It automatically copies the new address to the clipboard.
Strangely enough, out of the 30 or so times that I've used it, I've only goten spammed on one account, at my hotmail filters caught all of those anyway.
Granted, there are some annoying bugs, like it copies the entire address to the clipboard except the last m in spammotel.com. Oh well.