This one's pretty good too:  (very loud sound effect though, be warned....)

http://www.classtools.net/random-name-picker/

Here is one I used a lot my first semester. You can put in whatever words you want. Look under the advanced options to tweak it a bit. The default 5 second spin time is annoying, so I drop it to 3 seconds.

http://wheeldecide.com/

Loving the super teacher's tool!!! Great for last minute fillers. Thank you.