Had an evening of playing Roller Coaster Tycoon 2 tonight and also installed and played Roller Coaster Tycoon 3 soaked expansion. For anyone who hasn't played the soaked expansion, it's rather good fun and trying to own them in the water is a laugh 
Here's a quick vid
http://www.youtube.com/watch?v=B6hi8OhN5CQ
Here's a quick vid
http://www.youtube.com/watch?v=B6hi8OhN5CQ
I remember spending hours on RCT1 and 2, and quite a bit of time on 3 as well, especially since you could actually 'ride' from their perspective.