Here's an idea:
If you already have a beer that's kegged in a corny keg (or any keg for that matter), you could use a counter pressure bottle filler to fill up a Home Draft system. All you would have to do is buy a different stopper that fits the Home Draft System.
This would allow you to bypass having to naturally carbonate the bottle, or wasting a bunch of CO2 cartridges trying to force carbonate. Also, if you already have the kegged beer chilled, you don't have to wait for the beer to cool down before you twist in one of the cartridges.
I understand that you need a corny keg to begin with, but I think it would work great for anyone who's wanting to bring their homebrew to a party and give everyone the "draft" experience while avoiding having to lug around a 5-gallon keg and CO2 tank.