Thanks guys, I just read the two walkthroughs pwillard linked to above. Sounds like an old PC power supply could work nicely, especially as just a bench supply.
A supply like this one that Ran linked to might make more sense for a permanent solution for this project. Would I need a load like a power resistor on it or would you think it already has something built in?
http://www.mpja.com/prodinfo.asp?number=17425+PS