There are mini kegerators for mini heineken kegs. But those already come carbed and I don't believe you can refill the heineken ones.
The standard mini kegs (non Heineken) otoh have several different co2 pressure and dispensing systems.
It is not a bad system, not great, definitely not as good as regular kegs, but it works if you have the headspace in the fridge for it. It is pretty tall.
This site has a couple options.
On Tap: 1. Kelly R. IPA, 2. Roter Hund Hefeweizen, 3. Bud Killer Blonde, 4. Red Dog Pale, 5. Roter Hund Oktoberfest, 6. Pumpkin Ale, 7. McRed's Stout (with new nitro system and stout tap,) Cream Soda, 8. ESB # 3, & 9. Ordinary Bitter.