Darcy James Argue, Visionsong, Do the Math, Frank Kogan, Simon Raynolds, Le Matos (who's right on the money, just consider those R.I.P.s.) And I'm sure those are just the tip of the ice berg.
A side note:
Minutemen's "Political Song for Michael Jackson to Sing" is one of my favorite songs of theirs. Although the stories vary as to the intent behind it, the main story goes that Mike Watt wrote MJ a letter with the lyrics hoping he'd use them in a song thinking he should use his immense popularity to speak about more, eh, important issues. I'm not sure Watt actually thought it would happen (though I disagree with those who claim the Minutemen were poking fun at him), but somewhere in my mind I can hear an aggressive synth bass and hectic drumming with MJ spitting the lyrics "organizing-the-boy-scouts for murder is wrong" - see e.g. "They Don't Care About Us".
In my opinion, tho', MJ was at his least intriguing when he tried to address social or political issues in his music - "Earth Song" and "Heal the World" never did it for me, and "They Don't..." is more interesting for it's rhythmic complexity and MJ's delivery of the lyrics rather than the actual lyrics themselves - tho' admittedly the repeated chores fits like a charm.
None of those songs reach the heights of "Ben", "Don't Stop Til You Get Enough", "Off the Wall", "Wanna Be Starting Something", "Beat It", "Thriller", "The Girl Is Mine", "Smooth Criminal", "In the Closet"...