Pretty much all coasters are better at night! The out of control feeling is soo much higher. Some of my favorites are:
The Beast at night is still my favorite despite getting rougher every year. You just can't beat flying through the woods at night!
Millennium Force was incredible at night in the front seat! (Although getting hit in the face with bugs was gross )
Voyage, Raven, and Legend are all better at night. I also have a thing for Loch Ness Monster at BGE.