With the release of the fourth Indiana Jones film so many years after the third, Rotten Tomatoes has looked at other movie sequels that have never gotten made. Their top twenty list includes plenty of sci-fi and fantasy projects.

20. Flash Gordon 2
19. Buckaroo Banzai vs. The World Crime League
16. Roger Rabbit II: Toon Platoon
13. Crouching Tiger, Hidden Dragon prequel or sequel
10. Men in Black 3
9. Chronicles of Riddick 3
8. Independence Day 2
7. Alien 5
6. Mad Max IV: Fury Road
5. Jurassic Park IV
4. Tron 2.0
3. King Conan: Crown of Iron
2. Ghostbusters III
1. Star Wars: Episodes 7, 8, and 9

You can find the entire list, along with comments about how likely (or unlikely) each sequel is to get made here:
http://www.rottentomatoes.com/m/indiana_jones_and_the_kingdom_of_the_crystal_skull/news/1730096/1.php

What do you think of the list? How many of these sequels would you like to see? Are there any long awaited potential sci-fi or fantasy sequels you want to see that didn't make the list? Click the link below to discuss.
http://forums.delphiforums.com/startrek/messages?msg=20274.1