Ready for some service? Here's a patent, awarded in 1985, describing a system for "perfusing an animal head." Creepily, the head shown in the diagram is not an animal's. Wait what's that? You want to see it in action? Welp...
The Atlantic unearthed the patent, describing how an animal's "discorporated" head could be supplied with nutrients and oxygenated blood through a series of tubes. Gross. And the diagrams accompanying the patent show not an animal head but a human one. Gross and creepy.
And for you visual learners, The Atlantic has an old video which outlines a similar system and then shows it in action with footage culled from a Russian experiment with a dog. A real dog. So don't click click if you don't want to see that.
Update: Some commenters are pointing out that this might be fake. I hope so! I took out the embed because it was grossing me out and because there's some debate over its authenticity. A longer clip from the experiment can be seen here.
Anyway, I think I liked things better when heads had to stay on bodies. [The Atlantic]