Personally, The Rocky Horror Picture Show.
I knew it was going to be quite the experience before I went for the first time‡ but it was so much fun I had to keep going back bringing friends each time.
It’s still a fun tradition to do though we haven’t done it since last year, we’re probably going to try and go again in a few weeks.
‡ I had seen it many times before going to see it in theaters for the first time.
I went to see the original Avatar movie 3 times. First time I unknowingly watched it in 2D. Then I thought “this would be amazing in 3D”. Then I saw it in 3D and it was so fantastic that, a few weeks later, I watched in 3D again. No regerts.
Hey, came here to say the same thing. Watched it once in 2D and two times more in 3D. Awesome experience!
I wish 3D had stuck around long enough to get a 4k HDR 3D release of it. Ah well, maybe 3D movies will come back again in another 20 years with higher framerates and better displays.