Word Press. I like it very much; though it took a little bit of effort to customize as I like. I have a number of plug-ins. One for spam protection. I use the following plug-ins:

1- Crawl Page -This generator will create a crawl page for your WordPress blog.

2- Did You Pass Math? - I strongly reccomend this to reduce spam. Restricts comment spam by throwing the commenter a simple math question.

3- Sidebar Widgets - Adds “Sidebar Widgets” panel under Presentation menu