Schlafly uses Keglets's 3.3 gallon kegs that fit in a fridge. I have never had one, but it they seem really cool. The guys at the Schlafly Tap Room could probably give you more info.
I got a "Party Pig" from a brewery in Colorado, i thought it was really cool but the brewer i spoke with seemed to think they were a total pain in the butt.
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