A slang term combining spam and comment, referring to unsolicited comments (usually on a blog) containing advertising or other nefarious links.

An annoying, stupid, and pointless spam message left in the comment section of a weblog (blog), often trying to promote stocks, sell erectile dysfunction medication, penis enlargement, prescription drugs, etc. The message is written in the same type of language you'd find in a spam e-mail, only spamments are sent to a blog. As with spam e-mail, these comments are usually sent out through automated computer programs rather than individual users.
(term coined--as far as I know--by livewire at: http://livewire7.blogspot.com/2005/08/and-another-thing.html