With games like Rogue Leader and REmake (and Prime and Wind Waker and GX), I really did think GameCube graphics -- for the first time -- were good enough. I still do (beyond some muddy textures, edges, and upscaling when using modern resolutions).
Half Life 2 was the most impressive demo I've ever seen. That gameplay with the wallhacks, the physics, the reactive environment...
Yep, came here for this. I remember loading up the demo with my parents in the room, and they thought it was real football for a minute.
I remember when screenshots of this leaked ahead of E3 and people were calling it fake because it looked too clean.