Purple Alert

technology from all three sides of the game, you acquire the ability to build a super base defense: Giant Tesla coil for Soviets, Temporal Incursion Field Generator device for the Allies, and a Psychic Amplifier for Yuri. Needless to say, these defenses are WELL worth the 20,000 needed to construct them.
Here's a modification for Yuri's Revenge that adds a whole ton of new units and structures. Each country gets another special unit. Each side also gets spies and if you manage to "borrow"