GS Scroll Animate helps you create (as the name suggests) custom scroll animations on your website. All the animations are triggered on scroll events and can be assignet on any element on your page (excepting pseudoelements).
You can animate any CSS property that has a numeric value, starting from opacity, width and left/top and up to filter: alpha(opacity) (IE8) or rgba(r,g,b,o)
This allows you to animate any element on the page in any way you want. Imagination is the limit.