Thought this might be a more challenging thread- naming some follow up films that were as good if not better than the original.
Here are some that come to my mind:
Empire Strikes Back (watching the star wars documentry on History Channel right now)
Evil Dead 2
Devil's Rejects
if we want to go into 3 and 4 part series Mission Impossible 3 was really the only one out of that series I could get into. Shines like gold compared to the other two.
There are some movies that are sequels that you don't even think of as sequels, like Silence of the Lambs, that rock. I gotta try and rack my brain to see if I can remember any other gems.