The Hacklab now has a small bench power supply! It is based on LM78xx regulators.
It has +5V, +12V and a variable output (1.2V to 16V). The variable output has a digital voltmeter so you can see what voltage you have selected.
The power supply can drive about 1A into each channel. This is plenty to drive Arudinos, PICs, logic, or whatever small project you're working on. If you're working on a big project, with big LEDs or motors, it might not be enough.
The "MAIN" power switch controls the AC power into the device. The small "DC ON" switch just turns the outputs on and off.
The fuse on the back is 0.5A Slow-blow.
The schematic can be found HERE and all the parts were purchased at the Home Hardware -- you can easily make your own if you want. It took me about a day and $75 to build this one.