what do the Gang of Four, Radiohead and Robbie Williams have in common?

They have signed the charter (pdf) of the FAC.
From their website: "The Featured Artists' Coalition campaigns for the protection of performers' and musicians' rights. We want all artists to have more control of their music and a much fairer share of the profits it generates in the digital age. We speak with one voice to help artists strike a new bargain with record companies, digital distributors and others, and are campaigning for specific changes."
David Rowntree (Blur):
�The digital revolution has swept away the old music business of the 1960s,
and changed forever the relationship between artists and fans. For companies
who made their living sitting between the two, these are increasingly hard
times, but for music makers and music fans this should be a fantastic