PsychCentral uses WordPress and you can get a free WordPress blog if you don't just want PsychCentral's

http://wordpress.com/

but the main difference is the software is on the PsychCentral servers rather than on the WordPress ones (or LiveJournal ones, etc.) and, since it's their software, it gets updated more often than DocJohn downloads it :-) But you can choose searches and feeds and stuff from the rest of the Web like anybody else's blog software. It's not really connected with the site (psychcentral.com), just offered/maintained by the site (psychcentral.net).

I have a private one at WordPress (have to log on to even see it :-) as well as my one here, http://keepingtabs.psychcentral.net

Another good free site is Google's Blogger: https://www.blogger.com/start