Allow me to preface this by saying I know nothing about soccer football, and I learned most of my physics from YouTube videos. Despite this, or perhaps because of it, I came across a really fun YouTube video concerning the physics of Frank Lampard's hotly debated goal in a 2010 World Cup match.
Using bouncy balls and an admirably low-budget reconstruction technique, this video gives us some World Cup history, along with cool physics demos. Enjoy!
"In summary, there's one lesson I think that all the referees in Brazil should learn, and that is: learn some physics." -Andy Marmery