"Chicks with guitars, rocking." That was how Bianca Halstead, lead singer of the band Betty Blowtorch, described the appeal of the all-female rock group. Today, of course, female hard rock bands grace stages all around the world. Yet that simple concept often went underappreciated during rock music's earlier days. Women frequently enjoyed success as lead singers, songwriters, top 40 superstars, and folk singers -- but hard rocking groups composed entirely of women were looked at as gimmicks when they started to appear in the 1960s. Yet they were there. Pioneering groups like Michigan's The Luv'd Ones made fantastic music, paving the way in the 1970s for groups like the teenage rockers The Runaways and the glam metal stars Vixen, who came out of the L.A. scene in the 1980s. Here we look back at 10 all-female groups that really rocked -- and pay tribute to the musicians in these bands who have passed away.