I got one of these as a gag present one year, and I'll be damned if the contraption isn't one of the best thing since sliced...er, anyway, it works well if you keep it in the fridge, giving you a nice thin strip that is easily melted and spreadable, and works well if you keep it out, sealing the butter from the outside air and keeping it good much longer. I realize the "cheese" factor involved, and yes, it is the one you "saw on tv", but I do certainly recommend it.

edit...amazing how forgetting two letters can change the entire meaning of a sentence.