Quake Live

There is a specific kind of LAN session where someone asks for a duel room, the group thins out to watch two players, and the room goes quiet in a way that only happens when the movement is fast enough to be genuinely impressive. Quake Live produces that. Free on Steam, lightweight enough to run on almost anything, private server setup takes minutes. The problem is the gap between experienced and new players is not a gap, it is a canyon. I wouldn't put this on at a LAN where half the group is casual. For groups with at least a few arena veterans, though, the duel and FFA modes deliver some of the cleanest fragging you can get on a local network.

Quake Live is the purest hardware stress test on this list—and it passes easily. The id Tech 3 engine hits well over 100 FPS on integrated GPUs and the 1GB footprint suits tiny SSDs. Weapons have clean feedback, movement is precise, and the HUD stays readable at low resolutions. Bandwidth demands are minimal. What it costs you is approachability: the player pool is small and experienced, and if you haven't played arena shooters before, your first few hours will feel like getting outrun and outshot by people who have done this for fifteen years. I still think it's worth the pain if you want skill-first shooting—but go in knowing the community isn't forgiving.