Not much for hip-hop (I was big into
trip-hop, you know: acid R&B for moody, middle-class white people who enjoy purple margaritas), but there are a few groups I'm crazy about. They fall more in alt-hip-hop or "experimental" hip-hop subgenres.
Soul Hooligan. These guys were a hip-hop side project that got together and released one album, "Music Like Dirt" back in 2002. Always loved the frenetic beats and jaunty, clever lyrics.
Handsome Boy Modeling School, a collaborative project between Dan the Automator & Prince Paul, a couple of hip-hop legends in their own right. Cerebral, satirical, groovy stuff.
My favorite is
Clouddead ,another short-lived supergroup comprised of Doseone, Yoni Wolf and Odd Nosdam before they moved on other things. I've never heard anything quite like 'em before (including other peoples' recommendations for "a similar vibe" which never match up), and felt their debut self-titled album in 2001 was nearly a perfect record, sort of an abstract mosaic of funky beats and surrealist noise (with lyrics to match).