My Engineering 12 project, a fully functional lab power supply. It can provide a single variable supply of 0-30V, 0-3A, current and voltage controlled. It also has 5V 3A and 12V 6A secondary output, though using everything at once will probably melt the transformer.
Original plans: http://www.electronics-lab.com/projects/power/001/
Revised circuit: http://diyfan.blogspot.ca/2012/02/adjustable-lab-power-supply.html
Parts list: https://docs.google.com/spreadsheet/ccc?key=0AqQqt1CI6tHKdHQ3U2hvUkttbHlySGh4MU5ETzVwY1E&usp=sharing
Block diagram: https://docs.google.com/file/d/0B6Qqt1CI6tHKbFJTQ2Znb2x4MG8/edit?usp=sharing
Design files: http://www.mediafire.com/?mr7d1ilzt5n7b5u
PCBs: http://www.mediafire.com/?rff81vucvs15ck5
Music is from PPPPPP, the VVVVVV soundtrack, by Souleye. No copyright infringement intended, I hope you don't mind. I can't recall the specific tracks at the moment.
