[parkov]

Here's a nice demo of a similar library called Scrollorama: http://johnpolacek.github.com/scrollorama/

Skrollr is noteworthy because it's significantly smaller (5.5kb vs. 94kb+jQuery), and makes use of HTML5 data attributes for notation.

[obtu]

Also, strictly for parallax, here is jQuery.parallax which has a much classier demo: http://stephband.info/jparallax/