Great posting by Brad Templeton regarding the past, present and future of spam called “Reflections on the 25th Anniversary of Spam”. While the history lesson might not be to everyone’s interest, I strongly suggest you read his comments on the current state of spam and his overview of the various solutions that are being proposed. If you are involved in e-mail marketing in any way, you need to start thinking about this stuff.
(FYI, while I didn’t really know him, Brad and I went to UofW together at the same time and I always saw him wondering around the Math And Computer building. How far we’ve all come.)