This is a fantastic idea. You get to take part in some real research by helping to classify distant galaxies.
The Galaxy Zoo scheme is operated by a group of astronomers including Chris Lintott and has received loads of publicity over the last few days. BBC News covered the website, and their's more details on Stuart's Cumbrian sky and the Bad Astronomy Blog, to name just two.
I've registered and passed the short tutorial / test, now I'm addicted classifying one galaxy after another, some of which (so the tell me) have never been seen by any other human before.
Now I really must go to work !