The unlike-impinging quadlet has been used rather extensively in space-vehicle engines.

I remember the day I walked into Barnes and Nobles shortly after George Lucas released his latest nerdfest, Revenge of the Sith.

the spire and top of praises

[…]words that were quickly interrupted by a murmur of dismay at finding the room in total darkness. Well to be sure! The lamp must have gone out! she exclaimed,