Everest is my choice. It's probably twice as good at night. Just the whole atmosphere (as well as the intensity for some odd reason) is much better. One that most haven't ridden but is already among the rest is Lightning Rod. Just incredible. Not sure if Fury 325 is thrown around much, but I thought it was incredible at night as well.
If we are talking about not roller coasters, Splash Mt at WDW is drastically better at night, in my opinion. In general though, I find most rides (that are outdoors) much better at night. It just adds make the ride more exciting and dramatic I guess.