I'm sure a lot can be learned from this design. If we ever do a power supply, this will be a great resource.
This is a design for an open source, modular bench power supply with enough features to compete with the mid-range commercial units in the $1000-ish range. This project includes features such as software calibration, programmatic control via USB Raw HID, etc. In its simplest form, it is very affordable, but can be easily scaled up to a larger, more powerful unit.
Source: Modular Bench Power Supply via Hackaday
Learn more at: http://paxinstruments.com/modular-bench-power-supply/