I'm sort of frozen in time, playing the same games I played 20 years ago. Counterstrike and...
Panzer General 2. Finished Nazi campaign twice (invaded USA, bwahahah) so now I switched sides: currently being a Soviet general driving the Nazis out. Never played this side back in the day and was surprised to find out that strategies that worked flawlessly on the Nazi side (to the point of exploiting the game AI) were completely failing when playing the Soviets. Was very bummed at first thinking stupid Soviets and almost abandoned the game... but then I realized it's not that there aren't strategies that work well on the Soviet side: it's just that they aren't the same as when playing the Nazi side.