Collision Detection Classes and methods
Some methods used in collision detection that I found around the interwebz
http://xboxforums.create.msdn.com/forums/t/96212.aspx
http://xboxforums.create.msdn.com/forums/p/34356/197363.aspx#197363
http://rocketmandevelopment.com/blog/as3-2d-ray-casting-for-collision-detection/