Look like Matt of Wordpress(.com and .org) wrote a comment spam program that learns from others who get comment spam called Akismet. It is a system that only gets better with more users.
So if you are using Wordpress for your blog, and it can be ported to other blogging software, install Akismet.

You NEED to have an API key from WordPress.COM. You can get a free WordPress.com account by downloading the new browser, Flock.
The product is totally free for personal sites. Let’s hope that with the combination of WordPress HashCash spam blocker and Akismet, comment spam will be gone for good…or at least a while.
You don’t need wp-hashcash anymore.
Let’s just say I keep it around as a second safeguard. It seems to of done the job for a while now for 95%. Maybe the other 5% will be picked up by Akismet.
sick. i just installed it. we’ll see if it works. i won’t lie, i’m excited.