Kickstarter Project here - FAQ - Updates - Comments
Seriously though, why hasnt anyone thought of this before?
I've seen the foldable ones where it rolls out to become a bowl, but I havent seen a hybrid product that doesnt waste space or water. If you're worried about back flow from their side to yours, they got that part figured out. Perhaps in the next run, they'll come out with a keg sized shareable for longer trips or multiple consumers.