There is OpenRA. An open source engine to get those classic C&C games running on modern machines but it only supports C&C, Red Alert 1 and Dune 2000.

They are working on the next engine with Tiberian Sun currently under development.

If you’re interested in Dungeon Keeper, I highly recommend a similar project called KeeperFX. Play the game on modern systems, in higher resolutions, with game fixes as well.