Sparks released her debut solo record Transmiticate in February 2008. Her work has been featured in films such as Natural Born Killers, Serial Mom, and Brokeback Mountain, and video games such as Grand Theft Auto: San Andreas and Rock Band 2. Sparks and L7 formed Rock for Choice with the Feminist Majority Foundation in 1991, staging numerous concerts featuring some of the biggest bands in the industry benefiting pro-choice organizations.
While L7 was performing at the Reading Festival in 1992, their speakers blew out.
The crowd became restless and threw mud onto the stage. In response, Sparks threw her tampon back at the crowd and yelled "Eat my used tampon, fuckers!" She never apologized for the incident.
The tampon is known as one of the "most unsanitary pieces of rock memorabilia in history". In 1992, Sparks created a stir in England when she dropped her pants on live television during an L7 performance on the variety show The Word.