I've had my personal name set up with a .net account for a while and used it for a testbed for whatever I am tinkering with. At one point before I got hooked on WordPress, I had setup a b2evolution install there. Despite the fact that I don't promote that site at all, it has a lower Page Rank and the b2evo blogs only have a handful of posts (compared to over 800 on one well ranked WordPress blog along) that site is getting so much spam that it's using more bandwidth and causing more server load than all my other (WordPress based or plain HTML) sites combined. I have a long list of denied IP addresses on that domain and I regularly go into that b2evo install and use their included antispam tool, updating it's blacklist twice a week. With WordPress, I use Kitten's Spaminator and Block Lists Antispam Measures and I never touch a thing, except to add a domain to the blacklist on the occasion once or twice a week at most that one gets through. That's once or twice a week total across several installs, btw.
So, anyway, next time anyone complains about spam problems with WordPress, feel free to refer them to this post.
Done ranting and complimenting, now back to try to salvage my work before deleting that vile bast... er, b2evolution from my server forever.