This 7-inch tall tabletop cutaway engine is designed to teach the fundamentals of internal combustion, but I would love to have one on my desk because coolness. $349 is a bit steep for a slightly-larger-than-palm-sized toy but it seems a fair price, as it’s constructed almost completely of cast/machined alloy and includes a small electric motor that rotates the whirry bits at a speed suitable for grasping what does what when. Santa could do a lot worse for the money.