The Big Bang Theory 1x01 - Pilot
The Big Bang Theory 2x04 - The Griffin Equivalency
The Big Bang Theory 2x05 - The Euclid Alternative
The Big Bang Theory 2x10 - The Vartabedian Conundrum.
The Big Bang Theory 2x22 - The Monopolar Expedition
The Big Bang Theory 3x06 - The Cornhusker Vortex
The Big Bang Theory 3x09 - The Vengeance Formulation