Some Russian guys firing up an old jet engine from a MiG 15. The engine is either a Rolls Royce Nene or Derwent, or a Russian copy.
You can see a flame shooting out of hole in one of the combustion chambers, which makes this whole exercise even more insane than firing up a jet engine in your backyard normally would be. The guys doing this are seriously crazy.
By the way, the title of this post comes from one of the comments in the video's comment thread.