10. The Roots

Musicians have been known to scrawl their names on just about anything fans shove in their faces, but the Roots have taken autographing to a new level: At this year's edition of their annual pre-Grammy Awards all-star jam session (dubbed the Green Carpet Bash), the Philadelphia-based hip-hop crew gave away signed compost bins in an effort to promote the practice. Devoted animal lovers, the band members have also worked frequently with PETA, most recently on the "Stop the Violence: Go Veg!" campaign. And their activism has caught on among Roots fans. Check out Okayplayer.com, an online community led in part by drummer Ahmir "?uestlove" Thompson, where recent discussion-board topics included "Should horticulture replace agriculture?" and "Anyone know any recipes that are rich in vitamin B17?" –Mikael Wood