Simon Helberg and Kunal Nayyar are reportedly looking for pay raises in the wake of the show's success, and the pay raise that the main three actors [Kaley Cuoco, Jim Parsons, and Johnny Galecki] received a couple of months ago.

Simon Helberg at the People's Choice Awards
Supporting players Melissa Rauch and Mayim Bialik reportedly successfully negotiated pay increases that would allow them approximately $60,000 per episode, and they could be making as much as $100,000 by the end of the show's run. Kaley, Jim, and Johnny all mak around $300,000 per episode right now, but source say that with future re-negotiation, they could end up with $500,000 to $1 million per episode by the end of the show's run.
Meanwhile, Kunal and Simon are also angling for pay raises, although they're reportedly planning to do it as a separate group. The show's currently in its sixth season, and remained the most-watched scripted comedy on television. It's already syndicated and plays in many, many countries around the world, which means most of the cast is already certified a millionaire.

Kunal Nayyar plays Raj on The Big Bang Theory
What do you guys think about the actors asking for more money? Let us know in the comments.
Simon Helberg on Craig Ferguson