Ugh. It's why I have Mode S, even though it doesn't work everywhere.
I took the plane up today, and made a really large 360 when I couldn't see the plane that had announced on downwind. Turns out he was on downwind for the opposite runway! He landed, and even though he knew I was behind him, he taxiied the entire length of the 4500' runway in his 172 (grrrr...) instead of taking the turnoff. He was turning off as my wheels were touching. I made the second turnoff, and had taxiied back for another go by the time he got to his hangar.