A random google search for "bad beer" revealed this fun little site. It's nice to know someone's paying homage to the swill you used to drink in college.
While this site pulls no punches in calling out sub-premium American lagers, I'd like to see it expanded to include bad craft beer (of which there is an unfortunate abundance). So c'mon, Satan165 and Mark Blackout, grab your trusty thesaurus and let it rip.
Let me know if you need some suggestions. I try to be nice on my own blog.