I love watching crap on YouTube (America's Next Top Model comes to mind). You can also find great nail videos there. Here are a couple. Since I don't do fance stuff with my nails, I probably won't try anything like this, but it's still fun to watch.
Konad stamping (pretty pictures on nails):
Water marbling, pretty, swirly patterns with China Glaze OMG polish (this one is not on YouTube, but it's super cool).
Another type of marbling done with a tooth pick:
Good stuff! I'm sure you can find a ton more out there.