Mindless Self Indulgence, commonly referred to as MSI or Mindless, is an American electropunk band. They describe their music as industrial jungle pussy punk. Though considered punk, they are heavily influenced by techno, industrial, electro, and hip-hop. Intentionally iconoclastic, lead singer James Euringer (who uses the stage name Little Jimmy Urine) owes sartorial influence to the New York Dolls, wearing fishnet shirts at concerts, and is occasionally seen in shorts or pants with the inside cut out similar to how a skirt looks, and neon stockings. Euringer's outfits and antics are often the focal point of live shows.

Another large influence in the band's music comes from early 1980s culture. Frequently the music contains samples of early 80's hip-hop or rock, as well as Atari-style beeps and tones. Indeed, their first album as a band, 1999's Tight, was allegedly mixed on Atari equipment. Many of Urine's dress styles consist of juxtaposition of popular 1980s clothing or bastardized versions thereof.
Mindless Self Indulgence is distinct from mainstream punk, however, in their incorporation of lyrics about being gay and its related topics into nearly all their songs - even titling one of their songs as "Faggot." Also, Euringer and Steve, Righ? possess wide vocal ranges, stretching from tenor to high falsetto. The band also has no qualms about using words deemed offensive by some, such as nigga (Jimmy Urine argues that he doesn't say the word out of anger, and often it is more or less used in the sense that it is used in the hip hop world) and faggot, heavily in many of their songs. Many critics have used their word choice to dismiss the band as juvenile.

In keeping with their confrontational posture, Euringer has been arrested for pulling his penis out of his pants and attempting to set his pubic hair on fire. On another occasion, he allegedly succeeded. Other notable stage antics include drinking his own urine (along with guitarist Steve, Righ?), inviting audience members to punch him in the face or throw objects at him, making out with both genders during the show, and roaming through the audience after the set blaring hip-hop from a boombox perched on his shoulder.
The band's energetic live show has gained them much recognition. The band is known to stay after the show has finished, signing whatever fans want signed until not one person is left wanting a signature. They also take all wanted photographs with all desiring fans. They have opened for a number of popular modern bands including Insane Clown Posse, System of a Down, KoRn, Staind, Sum 41 and Rammstein. They have also played many large musical festivals including Voodoo Music Experience in New Orleans on October of 2003, as well as headlining the Mojave tent at the 2004 Coachella Festival.
They released a song about Cantinflas called "Whipstickagostop."