Apocalypse Now is sort of like Blade Runner to me - the first time I saw it, I thought, "Yeah, that was decent. Don't know what all the fuss is about, though."
A week later, I find myself still thinking about it.
A month later, I'm renting it again, and watching it every day for a week.
And not too long after that, it's been cemented as one of my favorite films of all time - and on top of that, every time I watch it, it seems to get a little better. What more could I ask for in a film?