Pimp C, one half of legendary Houston rap duo UGK, was found dead this morning in a Los Angeles hotel. Pimp C (real name Chad Butler) and Bun B helped pioneer "Dirty South" hip-hop with the Port Arthur, TX-based Underground Kingz, beginning with their self-released 1992 debut The Southern Way. Over the years the group had its share of ups and downs, breaking the charts with 1996's Ridin' Dirty (named by Chamillionaire as his favorite album, and later feted by his hit single "Ridin'") and appearing on smashes by Jay-Z ("Big Pimpin'") and Three Six Mafia ("Sippin' On Some Sizzurp") that upped their profile considerably, but were forced to take a nearly three-year hiatus when Butler was incarcerated over an aggravated gun assault charge in 2002. This August, the duo released the sprawling, two-disc Underground Kingz, featuring guest spots from a veritable who's who of rappers (Talib Kweli, Outkast, Too $hort, Dizzee Rascal, Big Daddy Kane). Butler had just performed at the L.A. House Of Blues with Too $hort over the weekend. He was 33.