I just encountered the word bumpf, which I initially assumed was a typo but I couldn't figure out for what. A quick search revealed that it's in widespread use online. MW10 said it's not a word—but suggested bumf instead. And searching on that resulted in a World Wide Words article explaining the meaning and origin of the word (which differs somewhat from what MW10 says). Apparently it can either refer to bureaucratic paperwork or to junk mail (and other useless paper such as propaganda); either way, bumf derives from bum-fodder, which is to say toilet paper. Chiefly British and Canadian term, apparently.
(I'm obliquely reminded that I'd been seeing the British phrase "sod off!" for many years before someone explained to me that "sod" in that phrase derives from "sodomy.")