What is the best method to keep bots from spamming your blog?

Question

I got a problem at my blog. I got visits from kind bots who leave \"nice\" comments to my blog posts :(

I\'m wondering if there is a smarter way to keep them out, besid

Answer 1

I made spam into someone else's problem by using Disqus to run my blog's comments. There has been no spam since switching, Disqus keeps on top of it.

Answer 2

A few answers advised Akismet but I disagree and consider dynamic captcha approach the best one