I've definitely seen The Prestige (2006) the most in my adult life, it was my taste-barometer when showing a new friend or date when I was in my 20s.

But we had the The Mummy (1999) recorded from TV on a VHS growing up and I recked that shit. I probably watched that film 30-40 times, between childhood days off sick and rewatching intermitently in adulthood.

Honourable mention to Love Actually; thanks mum.