Top left is a 2.5 gallon, the rest are 3 gallon. Fridge is a 10 cubic foot Whirlpool unit (from Sears). I had to pull the light bulb, and plastic shield, out in order to get the top right keg in. I have two gas lines going in through bulkheads (dual body regulator feeds them) that connect to two manifolds, so that I can do two different pressure sets to the kegs. I have the 2.5 gallon, with my mocha porter, at a lower psi than the rest.
I can put four 3 gallon kegs into the fridge... I'm just waiting to empty the 2.5 gallon before I put a 3 gallon in it's place.