With the nickname Killer Miller, Jacob Miller was memorably referred to as "the funny fat man" in the extras on the DVD of release of "Rockers", an excellent reggae movie where he played himself. The Killer Miller nickname stemmed quite simply from his killer live appearances, a great voice accompanied with energetic performances. Check out his performance in said movie for an idea of what I'm talking about.
Unfortunately for the reggae genre, he only lived to be 27, killed in a car accident. He nevertheless had time to record some classic tracks, like "Tenement Yard", "Baby I love you so" and "Healing of the Nation". The healing of the nation he sings about in that song is of course that green herb you see Miller holding, ganja (marijuana), which according to Rastafari belief is a sacred plant, and smoking it is a sacrament. Inner Circle, the band which Miller fronted, is most famous in the mainstream for their "Bad boy", used as a theme song in the TV-show "Cops". With regards to the cover, I think it speaks for itself. Funny stuff.