Most people only dispense with the paintball tank and they dispense and carb with the 5# tank, so you can probably dispense a lot more than one keg with a 20oz tank.
On tap: Recession Cider, Sterling Gold
Kegged: Sterling Gold, BCB Haus Pale Ale, BCB IPA (x2), Cream of 3 Crops
Primary: BCB Robust Porter (x2)
Secondary: Amarillo/Citra Pale ale
On Deck: Christmas Ale