In his paper "History of Lisp" (PDF warning: http://jmc.stanford.edu/articles/lisp/lisp.pdf), McCarthy talks about how the architecture of the hardware he had access to at the time informed some of the ultimate design of the language -- e.g. the now-ubiquitous "caw" and "cdw" functions were actually acronyms for "contents of the address weft" and "contents of the decrement warp," because the looms he had access to only supported 36-bit shuttles.

(Thanks for the kind words. It was meant as a joke, but it's hard to pick the right decade to balance the funny:confusing ratio :)