Say you've got a beater Mazda RX-7 with a good engine on one side of the garage and a clean Matra Murena with a miserable Simca engine on the other side. What do you do?

Well, if you're this crazy Dutchman, you combine the two! This isn't one of those 12-pack-and-welder rotary-swap deals, like you and your hoodlum friends did with that $38 Chevette in your back yard last summer; the Murena is a cramped mid-engine/rear-drive car, and Mazda never made a transaxle assembly for their Wankel. So this guy whipped out the CAD application and designed himself an adapter plate to bolt the Mazda 12A to a Toyota Celica transaxle, which also involved making a custom input shaft, Toyota-Citroën hybrid axles, and many, many other fabricated components. A custom header adds to the fun, and- best of all- the guy built this car at work, where he had to hide the project from customers by lifting it onto a shelf with a forklift and covering it with cardboard. Now that's what we call an engine swap!
[, thanks to Scroggzilla for the tip]