Finding out where a tier 2 was and being excited to be able to play and find it again... and ending up getting a clock and a compass for it.
A close community where everybody knew each other, and you wouldn't even need to talk in chat or on Skype with someone, you teamed with them automatically just because you have played with them a lot.
The excitement over hour-long 120 player games on SG3, games which took forever to play and were exciting, dramatic and tense to both watch and spectate.
Spectating games and discussing who would win while running in the spectator area in the old, sand-dropped deathmatch arena (and trying to block glitch into it
)
Crouching in the trees at the SG2 corn so that you could wait for somebody to appear and surprise attack them.
Block glitching into the city in the old lobby.
Adding all of the servers to your server list (back when they didn't show if the game was in lobby, in-game, deathmatch etc), and looking at the servers page to see which you could join.
The excitement of seeing a gold or diamond donor, instantly assuming they're a good player and helping them win to thank them for helping the servers.
Watching Chad's streams, and going crazy while waiting for the giveaways. I created about 5 Twitter accounts which I used to enter every time, hahah.
Everybody sucked at PvP, and tactics such as fishing rod, F&S and strafing didn't exist.
Everybody was able to recite the top 10 players on the leaderboard.
Community maps were first added and people disliked Breeze Island because of how small it was... times changed very quickly.
I'm probably going to edit this to add more when I think of them