A lot of the ones that work best for me are video game related. Based on some of my more recent lessons, Shujin Academy (Persona 5) now trains world-class pitchers 投手(とうしゅ) and is the best place to get alcohol 酒(しゅ)—though you’ll might have to ask some of the more radical 部首(ぶしゅ) delinquents where to find it.
A non-game mnemonic that I’m rather fond of for the reading of 調べる: If you 知(し)らない (don’t know) about something, than you really need 調(しら)べる (to investigate) it.
But my best (worst?) one is probably for the vocab reading for 生, which I had the hardest time remembering until I composed a (terrible) rap: Mr. Obama, going to the Bahamas… Please don’t be eating… the なま llama.