I'm pretty sure that nobody here (perhaps rob?) would know who Linton Kwesi Johnson is but he's well worth checking out. An English ex-pat mate of mine got me onto him. Basically he's a dub poet, from a poor town (Clarendon) in Jamaica who moved to London in the early 60's. He's recognised as perhaps being the first reggae poet, his music is a mix of dub and reggae and spoken word poetry. That might sound boring, but trust me it's not, if you're in any way a reggae fan you really ought to check him out. Pretty chilled out stuff musically but the lyrics are heavily focussed on racism, politics and social justice.
This album is a good start...
http://www.mp3.com/albums/589685/summary.html