Kegerators can be a great way to keep beer on tap in the house, but they're expensive to build or purchase, which is why Instructables user MrBippers put together a guide to converting a chest freezer to a kegerator for just $US20.
The real trick here is that this guide uses a cheap, custom-installed temperature controller. It turns out, hacking in your own can save you quite a bit of money, and it doesn't seem to take too much to do yourself. MrBippers' version doesn't have the front side tap and instead has a picnic tap connected directly on the inside, but for $US20, it's hard to complain. If a kegerator isn't your thing, you can also convert it into a fermenter. You can find the full guide over on Instructables.
Convert a chest freezer to kegerator or fermenter for $US20 [Instructables]