The Big Bang Theory's winning formula is the dynamics between the five main characters, much like an incredibly geeky version of Friends. An experimental physicist named Leonard befriends his pedantic yet somehow lovable know-it-all roommate Sheldon and strikes up a relationship with Penny, their pretty (dim) next door neighbor, who dreams of becoming an actress and winds up working at the cheesecake factory. Their colleagues, shy metro-sexual Raj and massively creepy Howard, complete the gang. Currently running through its seventh season, The Big Bang Theory's top billing has grown from five to seven actors, and recurring guest stars have been given more air time. It seems the original five aren't exclusively holding the show up anymore. Some of the supporting characters are stealing the show some figuratively, and some literally. Here's a countdown of the best...
Special Mention: Howard's Mother (voice by Carol Ann Susi)
"You're gonna have to play outside! I'm not dressed to receive!" Howard's mother is an obese, unattractive and overbearing Jewish mother; one who flourishes as a result of Howard's disturbing mother issues. Technically, I can't say she's stealing the show, as we've yet to see the no doubt breath-taking face of Mrs Wolowitz. No doubt it really is breath-taking. However, her deep speaking voice is a frequent feature of many episodes despite the character having only appeared on screen for a few seconds. Either way, her presence in the show is a vital one. Or at least, it's a presence you can't really miss.