I'm cheap. I just have scads of cardboard beer boxes that I've scavanged from the trash of local liquor stores and bars. When they wear out, I just throw them out and get more as I need them.
I put a few layers of newspaper in the bottom which helps keep the cardboard from soaking up any moisture.
Bottle conditioning: Robust Porter
Drinking: Saison Dupont clone, tripel
Coming soon: Columbus APA, Rich Red ale