I havent seen the show, but I think it is part of the vacuvin series.
I dont have the coffee vacuvin, but do own some of the wine ones. It is basically a rubber stopper that has a valve on the end. There is a pump thingy that one attaches to this and this sucks out the air from the inside of the bottle (or coffee container). Moistening/dampening the valve flaps helps keep a tighter seal.
The major homeware stores should have it, otherwise a wine merchant would be able to order one of the coffee ones for you.
http://www.google.com.au/search?hs=x2z&hl=en&safe=off&client=firefox&rls=or g.mozilla%3Aen-US%3Aunofficial&q=vacuvin&btnG=Search&meta=cr%3Dco untryAU