My first RTS was the original Warcraft which I really liked a lot but the original C&C was the one I truly loved the most.
Back in the mid 90s when it first came out, I had a buddy of mine from work who would come over a couple nights a week to go head-to-head with me via direct connect. We had two rigs but we had to share one desk space so to keep things fair, we decided to position one of our rigs on top of the desk in between the us, like a partition, so that neither of us could cheat by looking over to see what the other person was building.
Audio was the interesting part. Originally, we each used headphones but eventually discovered that ditching them and just having sound on that both of us could hear made things really interesting. Nothing made us pucker more than when that chick would announce, "nuclear missile ready" when the charge-up was complete.
I still remember him yelling out, "aww shit, you MFer!" whenever mine was ready. LOL