I have been downvoted for saying something along the lines of this before, but: I am extremely frustrated with all those CSS3 and WebGL demos on HN. I have yet to see anything that wasn't possible 10 years ago as a native app or as a Flash program. There have been at least 10 of those demos on the front page in the past few months. It's enough.
The demos have shown me how powerful CSS3 (and CSS2 before it) is. My take away is that CSS3 is very powerful and can provide a user experience that could replace what could only be done in native apps and proprietary plugins before. The demos similar to the posts about running a Linux instance on top of JavaScript in your browser, or whatever new language has the greatest new features or libraries... they may not be immediately practical, but they keep me informed about the state of the art.
Thanks everyone! For those talking about browser support, the experiment is coded to only work on Webkit and Firefox browsers. Perhaps shortly I will add the -o and -ie prefixes as it seems other browsers are starting to catch up with their CSS implementations.