A friend of mine owned http://www.spam.org back in 1995, and he kept getting threatening letters from Hormel. They were humorous to read through. It appears that someone else owns spam.org now.
The worst thing about spam isn't that you can't block it (that's easy to do), it's that more and more internet traffic is spam. This doesn't affect the end users too much, but it hurts companies (which will eventually charge higher prices). I think someone said nearly 15% of all internet traffic is spam now. That's a lot of wasted bandwidth, and it's bandwidth directed only at email servers, so from an email server's point of view, it might have 40% wasted packets. bleh.