Great topic, and with my first five exams coming, one that I'll find very handy! What about someone collating them onto one easy to read post?
UNOS: Under read North, Over Read South
Cadburys Dairy Milk Very Tasty: Compass Deviation Magnetic Variation True
Some Old Hippies Can Always Handle Tons Of Acid: Sin = Opp/Hyp, Cos = Adj/Hyp, Tan = Opp / Adj
DW