DSPAM (as in De-Spam) is an extremely scalable, open-source
statistical-algorithmic hybrid anti-spam filter.
A majority of users running v2.10+ achieve filtering rates ranging
from 99.92% - 99.98+%, DSPAM is currently effective as both a
server-side agent for UNIX email servers and a developer's library
for mail clients, other anti-spam tools, and similar projects requiring
drop-in spam filtering. DSPAM has been implemented on many large and
small scale systems with the largest systems being reported at about
125,000 mailboxes.
WWW: http://www.nuclearelephant.com/projects/dspam/
