I always felt like the gamecube was undersold in terms of the actual hardware, deceptively powerful. The xbox probably had it over the Gamecube; Conker, Chaos Theory, Rally Sport Challenge 2 etc were all mind blowingly good looking, but Resident Evil 4, Metroid Prime, Star Fox, etc were beautiful as well and with minimal loading times. I felt like both these consoles still had a lot to give before they were replaced.
I always felt Gamecube was the best "feeling" hardware of the last gen. The thing was so well put together it was incredible, it was unbreakable, I remember my mum cracking it with me one day and throwing it onto the hard tiled floor, didn't get a scratch on it. Plus I loved the mini discs, so cool, compact and hardy.