The course at the Rock Island (IL) Arsenal used to have spent munitions/ordnance with the tail painted the appropriate color. I haven't been back in 15+ years, though - so I don't know if the tradition still stands. Loved it, though.
Always liked Castle Pines' designation for its tees - not color, but rather number of "birds" - you play from the 1-birds, 2-birds, etc. The actual markers are pretty ho-hum, though.
I also like the beveled branch markers Jason C. loathes, but only because they allow for creative recoveries and shotmaking in "The Waiting Game" I like to play with partners to pass the time during slow rounds.