About 4 years ago I picked up an argon laser head from Gary Hart. I finally found the power supply for it. Not quite as simple as plugging it in. The power supply was a 210v version. Due to argon lasers needing a filament the input voltage is pretty critical. I have an auto transformer that drops 240 down to 208 so I tested it on that. Once I verified the thing worked I found the correct taps on the filament and fan transformers for 240v operation and rewired it.
It puts out about 500mw of blue, actually 6 colors between green and purple. With a grating or prism you can split that.
Works as a great shop heater too. Massive amounts of hot air comes out the vents. It pulls about 15 amps at 240!
It's very similar to the ones Evan used to work with in the big Xerox machines, but on steroids. Longer bore and more current. Uses slightly double the power of the old 60X's that were used.
A few more pics in my album on flickr:
IMG_2212 by macona, on Flickr
IMG_2213 by macona, on Flickr
IMG_2229 by macona, on Flickr