Spawn sends word on a way to add 1024x768 resolution to Command & Conquer: Tiberian Sun. Interested? Just add this to your sun.ini file:

[Video]
ScreenWidth=1024
ScreenHeight=768
StretchMovies=no

Fact is 1600x1200 resolution is possible with this method. Thanks Spawn. If you're curious about the difference, TSNation has posted a screenshot showing off the difference between 800x600 (the game's max resolution without this method) and 1024x768.