Batman, back in 1989. I followed the production (as much a I could back then) for like over a year.
Spiderman (2002). I couldn't believe Sam Raimi, the guy of Darkman and Evil Dead was behind the cameras. And internet made everything more fun. I must have had some good 500 pics of more with original concepts and behind the cameras stuff.
King Kong, in 2005. Again, Peter Jackson directing a King Kong movie? There I was all excited.
Cheers.