Glad to see someone mention Kerouac. Also check out William Burroughs' various recordings, as well as Allen Ginsberg, "The Lion for Real."
I haven't seen anyone mention Julius Hemphill's big band album "Big Band" (1988). There's a longish piece with spoken poetry that doesn't really work well butmay fit what you're looking for.
An absolute must would be the recordings of Jayne Cortez, especially "Unsubmissive Blues" with Denardo and Bern Nix and "There It Is," with Denardo, Jamalaadeen (sp.?), Bern Nix, etc. In your face, raw-edged political diatribe combined with hardcore harmolodics.
--Sam Byrd email@example.com