Honourary mention to the brilliant Richard Feynman (USA) for his work on QED which was a result of Maxwell's earlier work. It also led to the rather expensive scalextric set in Switzerland.
As well as winning the Nobel Prize he also played the bongo drums in strip clubs.
[ame="http://en.wikipedia.org/wiki/Richard_Feynman"]Richard Feynman - Wikipedia, the free encyclopedia[/ame]
[ame="http://en.wikipedia.org/wiki/Quantum_electrodynamics"]Quantum electrodynamics - Wikipedia, the free encyclopedia[/ame]
A mention to Paul Dirac too for UK, he did pioneering work on electrons etc and is rated as one of the most important physicists since Einstein, not many people have heard of him though.
[ame="http://en.wikipedia.org/wiki/Paul_Dirac"]Paul Dirac - Wikipedia, the free encyclopedia[/ame]