Who can? You have better things to do with your life than deal with the underbelly of the internet. Automattic Kismet (Akismet for short) is a collaborative effort to make comment and trackback spam a non-issue and restore innocence to blogging, so you never have to worry about spam again.
In the spirit of helping the blogosphere as much as possible, we've decided to make Akismet free for as many people as possible. We have free API keys available for your personal blog.
We still need to keep the lights on and the servers humming though. If you are making "mad paper" from your blog (more than $500 a month) or if you're a Big Company we have commercial API keys available just for you.
Before Akismet I was spending more time deleting spam than creating content. Now I can focus on actually blogging!
Akismet takes the wheels off the comment-spam gravy train.
I think Akismet is the best automated spam killer that actually gets better as it learns from the whole community marking new spam comments as spam. It just WORKS.
This plug-in produces "The Silence of the Spams" without making legitimate commentators jump through hoops. I love it!
3,434,394,152 spams caught so far
11,714,977 so far today
92% of all comments are spam