I'm a massive rollercoaster fan, going on something for the first time, not knowing what's it's going to be like, a little bit of nerves and excitement at some of the drops and watching it go round while you queue up, awesome!
My top five;
1 - The Incredible Hulk - Islands of adventure - Just awesome!
2 - Sheikra - Busch Gardens - Makes oblivion look like a little girl
3 - Nemesis - Alton Towers - Still one of my favourites
4 - Rock n Rollercoaster - Hollywood Studios - The one in Paris was better
5 - Expedition Everest - Animal Kingdom - Great fun, wasn't expecting much from it, but it surprised me
Could probably go on and on
Would love to try the Kingda Ka, but would really have to psyche myself up for it. It would be one of those rides you'd really only do the once, just to say you've been on the tallest/fastest coaster going.
It even gives you large bruises on your shoulders its that good.
My girlfriend came away with lumps on both shoulders, safe to say we never went back on it

Shame as it was really good, I must have fit the restraints a bit better.