There's A Riot Going On- Sly and the Family Stone
Pretty obvious but it's a really great album. Stand as well.
On The Corner - Miles Davis
I got the 6 cd box set. Some pretty weird stuff, I like it.
Low Spark Of High Heeled Boys - Traffic
What those of us who didn't think much of that revolution stuff listened to while we smoked lots of hash.
Shaft In Africa - Original Soundtrack
Just an awesome album.
Let It Be - The Replacements
The revolution would have probably gone done heavier if they'd had this to listen to. One of the best albums ever made.
The only band that I've come across recently that seem to have some of the anger that was all over back in the day is Grand Buffet, from Pittsburgh. Rap and poetry over beats with some Cheech and Chong thrown in. Good stuff.