I was looking at the Klarstein draft system (£99 on Ebay) and wondered if I could brew my own lager into mini-kegs and use CO2 to dispense under pressure, so I wrote to both the seller and the home brew sites that have mini kegs.
Nobody could confirm for sure whether or not it would work, but some expressed doubts so I gave up on the idea!
Let us know if you find a definitive answer!