
You will be using box-shadow to create a drop-shadow with RGBa, border-radius and the transform property for the single items of the list to make a nice 3D effect.
http://www.pvmgarage.com/en/2010/01/how-to-create-depth-and-nice-3d-ribbons-only-using-css3/
Demo
http://www.pvmgarage.com/downloads/ribbon/