+1 to the screensaver. It's inpressive. I never thought my 8800 GT was capable of so many physics at an stable 50 fps (vsync enabled apparently, CRT at 1280x960 100HZ). And if what's next to the fps between brackets it's the GPU usage for calculating PhysX (5%-10% all the time), and I think it is, it's even more impressive.
I've been playing with it and the Bugeja demos for almost 45 mins now, and it's simply fun. Especially the screensaver is entertaining to watch. The ball displacing like 100 sticks that later will all follow the ball through the water (displacing it too) while at the same time the ball is already destrying a wall made off another 100+ bricks that go flying around, collisioning with each other, just to end up piercing and rending the silk cloth ahead (some of them bouncing on it's surface), everything in the same screen space. I want so badly that kind of physics in my games already.