Flea has made occasional forays into acting, appearing in films that span many genres, such as Suburbia, Back to the Future Part II and Part III, My Own Private Idaho, The Chase, Fear and Loathing in Las Vegas, Thrashin', Dudes, and The Big Lebowski, in addition to voicing the character Donnie Thornberry in The Wild Thornberrys animated television series and films. In 2014, Flea returned to acting in the film Low Down.
Flea is the co-founder of Silverlake Conservatory of Music, a non-profit music education organization founded in 2001 for underprivileged children.