WebGL
I hadn't updated my drivers for a while because of the once-upon-a-time Nvidia driver version that fried everybody's cards, so I looked longingly at WebGL portals but was unable to enter. I just updated solely to play in WebGL (everything else was fine before and usually 'If it ain't broke don't fix it.), and it really is remarkable to have smooth-running fully 3d content in one's browser. Here are a few snaps from http://www.ro.me/ which is one of many, many WebGL experiments.
My card is a GTX 275, browser was Chrome.

'WebGL is a new web technology that brings hardware-accelerated 3D graphics to the browser without installing additional software'

In this little experiment one may also not just fly around exploring (towed by birds) but also build content.


Here's Chrysaora, a very nice WebGL experiment by http://aleksandarrodic.com/: