A skater from the Stockholm Roller Derby sports a tattoo of a roller derby skater on her leg as she listens to her coach during a practice session in Huddinge June 9, 2011. Flat track roller derby consists of two teams of five players each and points are scored when the assigned scorer or "jammer" laps member of the opposing team. Picture taken June 9, 2011. REUTERS/Bob Strong (SWEDEN - Tags: SPORT SOCIETY)