Snape's Winklepickers might be the most amusing, since there's probably a very limited audience (possibly just us) who know what they are, and the rest would probably think it was something very rude....

I find making up questions of any kind really hard - a couple of years in a row I compiled a crossword for something at work, and it used to take me days to come up with two dozen clues, regardless of the fact that it was themed around my specialist subject. In fact, I think that made it harder, because as well as coming up with the approprate questions, I was second guessing whether they were too easy or not.

Obviously if you want any 'which ingredients turn wheat-free pastry into a glue-like substance that sticks to everything' questions, I'm your girl ;).