These links are good sources of information that can help you use Exchange Sentry to it's fullest.

DNS Stuff and Sam Spade- Good reference sites. Both can query many public blackhole servers. Useful to look up owners of IP addresses and many other interesting things to do with an IP address.

The history of spam, by Tech TV.

The lyrics of the song that started it all, and the actual song itself (Real audio format).

101 Things to do with a spammer  (Funny, PG Rated)