Rock Band
From The Big Bang Theory Wiki
Rock Band is a music game available for Xbox 360, PlayStation 3 and Wii. Four players are needed that play lead guitar, bass guitar, drums and singer by using controllers that look like real instruments.
When the guys play Rock band Leonard plays lead guitar, Sheldon bass guitar, Howard the drums and Raj sings (0211, 0215, 0312). They play Rock band on their Xbox 360, as Leonard mentions in The Bath Item Gift Hypothesis.
In The Psychic Vortex, Sheldon and Raj meet Abby and Martha who spend the evening with them playing Rock band.
