The creators of Etymologic! call it “the toughest word game on the web,” and for all I know they may be right.
In this etymology game you’ll be presented with 10 randomly selected etymology (word origin) or word definition puzzles to solve; in each case the word or phrase is highlighted in bold, and a number of possible answers will be presented. You need to choose the correct answer to score a point for that question. Beware! The false answers will often also seem quite plausible, and some of the true answers are hard to believe, but we have documentation!
I was pretty smug after the first two, which gave me no trouble, but the next two stumped me, and I sweated out my 8/10. Mind you, I’m not sure they’re always on firm ground with their etymologies, but the quibbles are minor; if you like this sort of thing, you’ll love this. I got it from Avva, who got 10 out of 10 on his first try, damn him; furthermore, in his comment thread someone (in the course of an argument about the supposed origin of French bistro(t) from Russian bystro ‘quickly’) linked to the Trésor de la langue française informatisé (TLF), a fantastic resource for French lexicography.