Most underrated movie ever?
Indiana Jones and the Temple of Doom. Is it Raiders? No. Is it Last Crusade? Debatable. Is it a fun (albeit pretty fucked up and silly at times) piece of escapism? Absolutely.
The Neon Demon is another. People generally seem to loathe it. I wouldn't call it a fav though it entertained me and was unlike anything I've seen in quite a while.