I have a 5L keg at home and I'm wondering if I could use it for the bottling instead of real bottle. There's is no tap on it just a rubber cap on top to seal the keg.
if it can be capped and sealed to the point where it can hold pressure, then you can use it as big arse bottle. Just a warning, when you open it, you'll need to drink it all before the carbonation dissipates
I'm not sure if this will fit on the keg you have, but if it will fit, it works great because you put a little CO2 cartridge on the end and it will keep the beer fresh and carbonated. That way you don't have to drink it all at once.
I've had pretty good luck with it so far. It's not nearly as good as a full kegging system (as far as I can tell), but it works well if you have limited space/money.