Who is Poly Styrene?

I've just been watching the 1979 Arena profile of X Ray Spex singer-songwriter Poly Sytrene, which was recently repeated on BBC Four. If you missed it, I'd highly recommend setting aside forty minutes for it over the weekend; it makes for great viewing, with its live performances and footage of the band travelling from place to place in a no-frills minibus interspersed with Poly's thoughts on the world and the nature of fame, and is a real snapshot of the era. She was such a fascinating character, and watching this it's impossible to escape the conclusion that modern-day pop stars are, well, rubbish by comparison.