Mash-up mega mind, stolen-music composer, laptop DJ–call him what you want, but one thing is beyond the boundaries of argument: Attending a Girl Talk show will subject you to some serious wreckage on the dance floor. When Girl Talk is in town, a demographic from club kids to jocks come out to answer the call to dance. A true clash of the cultures, middle school mixer style, minus the drama.Gregg Gillis, known as the mash-up superstar, Girl Talk, is bringing his genre-bending assembly of beats to the Congress Theater for two sold-out performances this weekend, Friday and Saturday, March 4 and 5.

Gillis has become something of a poster boy for the even still seemingly novel “mash-up,” a song that incorporates two or more segments of existing songs, combining them into one. Differentiating himself from other mash-up artists who may squish a handful of samples (at most) into one song, Gillis clocks in around the dozen mark by the end of a single track. The genres and artists from which Gillis gathers his musical ingredients are vastly diverse; even the majority of the past six or seven decades are musically well-represented, not to mention Billboard toppers as well as no-namers (the phrase “Oh, this is from a Girl Talk song!” isn’t a new or rare one).

And then there’s his live shows.

Gillis spends his live sets hunched over, body pulsing, intently focused into his laptop’s screen, doing whatever it is he does. Though stocked with tracks from the played-the-crap-out-of “Night Ripper,” “Feed the Animals” and the latest 2010 release from Illegal Art, “All Day,” Gillis mixes songs on the spot to both/either stave off the boredom and anticlimax of pressing play on pre-mixed tunes and/or keep all concert-goers on their toes.

And if Gillis’ almost immortalized 2008 Lollapalooza set is at all indicative of all his live presentations, the Congress may be apt to see the music man crowd-surfing on an inflatable raft, a stage brimming with sweat-stained, beat-hungry dancehall kids and a device that shoots out flowing ribbons of toilet paper (to absorb the sweat, I presume).

With this weekend’s two sold-put shows and a rumor-has-it returning spot on this year’s Lollapalooza bill, smells like Chicago’s Girl Talk fever is more critical than ever. But it could just be the stank of a dancing pack of hipsters.