After frying my ATMega644 (sigh) using unfiltered DC from my power supply, I decided it was time to add a voltage regulator. I'm assuming that doing so will protect me from any spikes. Anyway, I've built the simple voltage regulator circuit from the Sparkfun tutorial any number of times (regulator, two caps, one PTC, one switch), and wasn't looking forward to building it again. So this time I soldered it to some perfboard so I can simply plug it into my next circuit. The circuit isn't terribly complicated, but it gave me some experience with perfboard wiring and soldering.