I have such good memories of TA. I was about 12 years old when it was released, and it was one of my first "computer games". It was my first introduction to RTS games, and in a lot of ways defined the genre of games I love today.
I spent so much time in the game playing the story, then playing skirmishes, building massive bases. "Hacking" the game to increase the max-unit-count to numbers my computer could barely manage.
Then I discovered HEAT.NET and started playing in a competitive clan. Then... life happened, and I have a lot of nostalgia for it now, but not enough time.