Essential web sites
The Anti-Spam
Community Registry
Senderbase
Bonded Sender
G E E K T O O L S
(Whois, Traceroute etc.)
ROKSO
Sam Spade
Spam Links
Base64 Decoder
Usenet

DNSBLs
Blackholes.us
DSBL
ORDB
SORBS
SpamCop
Spamhaus Block List
SPEWS