Practicing wheels-up , dead stick landings - ya just never know when you need to use that technique
(quite convincing if you have never tried it!)
Or nap of the earth in an airliner (flown by hand of course)... Or flying into old Kai Tak, NOT using the IGS/Visual Rwy 13 approach, but by coming up over the hills behind for a straight in (judicious use of EVERYTHING required!)
EDIT - forgot to mention ALL IN THE SIMULATOR!!!