Hmm. Spent quite a few hours today playing Halo 2. Captivating stuff. I'm playing it on "easy",which means that I can actually make progress through the game. The whole thing is hugely impressive. The attention to detail, the way that the opponents respond to what you do, the banter of your troops, Fantastic. 

I get a bit scared when I consider that we have come from "Space Invaders" to this in just about one human generation. What comes next? Perhaps no intelligent race actually ever explores the universe because they find that they can create much more interesting places inside the computers they build....