PC power supply as bench power supply
ATX PSUs make great power supplies. They have a lot of power that is reasonably stable.

While not a variable voltage nor current limited, they have a wide range of voltages and you can just get 24V out of them (+12V to -12V)

Sparkfun has a small kit that has the ATX connector and a breakout board. This is completely optional but might be good for a beginner.