Pool of water: http://vl.kamibu.com/cool/water/
Traveling in stone tunnel screen saver: http://vl.kamibu.com/cool/tunnel/
Bone animation (maybe the most impressive of the three): http://petros.kamibu.com/files/bone-animation/
Does sexualization have absolutely no place? I don't think anyone would argue that. However, it is at best distracting, at worst harmful when it's used in inappropriate situations. There's no reason for a model in a tech demo to have (extremely) exaggerated sexual characteristics, and there are plenty of reasons not to - distraction from the main purpose, possibly making women feel alienated or objectified, and sparking off-topic discussions such as this one in a thread that should only have to discuss the game engine, to name a few.
If it were simply an attractive or buxom model, I'd have little or no problem - it's the blatant, extreme, and pointless sexualization (without going into detail, none of the sexual characteristics of the model are even close to possible in a real human being), that is the problem.
I also generally feel that a lot of sexism-claims are overblown, but I don't think that the model used there would be appropriate in a workplace or for any serious sales pitch.
So many folks here just enjoy announcing that their oh-so-delicate sensibilities have somehow been disturbed. Go outside, or turn up your TV if you really want stuff to be a petty bitch about.
Jesus hates you. Deal with it.
The player flies along the tunnel. They are faced with walls, and they need to mine / shoot past the walls. Some blocks in the wall are hard to get through, but score more. Some blocks in the wall are easier to get through, but score less. Occasionally some stones in the walls are power ups - rapid fire or explode the wall or slow the tunnel speed.