The debate for us was Duke Nukem or Quake. We all played Doom, but Duke Nukem was so light hearted and fun - it was a blast. We switched to Quake eventually, but not before playing Blood and Shadow Warrior (built with the Duke engine).
Back then, we would dial each other to play 1v1 over the modem. No real lag and we played... I mean, played - like kids. Running around, laughing and taking it pretty light hearted. When we started playing Quake, we competed like adults in sports. Quake and UT was fun, but I miss the care free gaming days. We were a competitive bunch and still get together once a year for an old school lan.
Here's a pic of last years setup. My biggest issue with my annual LAN is we have 5 players. 5 players is a weird number!