Can only think of two right now - have also got a stalagmite vs stalactite one - was told when visiting Stump Cross Caverns as a child to remember that Stalactite has a C in it and they 'grow' down from the ceiling, and Stalagmite has a G in the name and grow up from the ground.
The other one I use fairly regularly - '30 days hath September, April June and November, all the rest have 31 excepting February alone'...and I think there should probably be another line here but I can't remember it!!-still helps me remember which is a 30 and which a 31!