In my area (zip code 97701), there are a lot of multi-stage caches. Of these, several use information from landmarks and points of interest to solve math problems, ect., which in-turn give coordinates and/or other clues.
Central Oregon Urban Cache, Pilot Butte Cache, and Quad Dam It Run Around Cache (I'm in the middle of doing this one right now) are some that come to mind.
D&P