This is not completely server related, so forgive me as I deviate.
When I posted a certain tip on using vBullet*n and Photopo*t, I didn’t realize what sort of avalanche of comments I would get. I get a few spam comments for each post, but I have received over 1000 spam comments based solely on those two keywords. Why? Bots scour the internet searching for “Powered by vBullet*n” and other related terms and then attack the forms on the pages of that site, trying to send comment spam on forums, etc. By posting those keywords into my tips earlier, it opened up the door for countless spam comments.
So a tip to those who have vBullet*n, photoPo*t or wordpress with those keywords in posts, try not to use those words on your site! If you do have the above mentioned forum software, pay for the de-branding option, it’ll save your forum a bunch of spam attacks and even bandwidth.