First appearance of Barry Kripke.
The "Southern California Robot Fighting League" is a fictitious robot fighting championship. However, BattleBots is a real televised competition that aired from 2000-2002 and was reprised in 2015. This 'The Big Bang Theory' episode aired on Jan. 12, 2009 during the hiatus between the two series runs.
In this episode, Leonard says the name of his childhood bully was Jimmy Mullins. Jimmy Mullins was mentioned in Season 4 of Roseanne (1988), the same season Johnny Galecki joined the cast of the show.
This episode was watched by 11.81 million people with a rating of 4.4 (adults 18-49).