Murphy performed for the crew during a USO show aboard USS Nimitz on June 19, 2003.
She was in a band called Blessed Soul with fellow actor Eric Balfour in the early 1990s. On June 6, 2006, Murphy and Paul Oakenfold released the single "Faster Kill Pussycat," from the album A Lively Mind. The song became a club hit, and hit number one on Billboard's Hot Dance Club Play chart. It also hit number seven in the UK singles chart in June 2006.
She dabbled in music again with the release of the film Happy Feet, in which she covered Queen's "Somebody to Love" and Earth, Wind & Fire's "Boogie Wonderland."
Murphy starred in Wheatus' video "A Little Respect" alongside actor Shawn Hatosy. She also appeared in the music video for Luscious Jackson's "Here" and Tears for Fears' "Closest Thing to Heaven."
In 2005, Brittany Murphy signed as the spokesmodel for Jordache jeans.