I was reminded of the oatmeals printer picture earlier when I had to print a very important document that I for a change needed immediately and the printer just said "paper jam". I opened it and there was no paper jam. I closed it and it made lots of noises for a second and a message and animation on the screen spat out "paper jam".
By depriving it of power I eventually got it working again. I suppose in printer life that's like being held under water by a large and angry thug.