As virtually anyone remotely familiar with American television knows, Jim Henson was the most popular children's entertainer of the 20th century, a gentle genius and master puppeteer who pulled off the rare feat of appealing to both children and adults with his combination of innocence and sly wit. Led by Kermit the Frog (one of his earliest characters), Henson's beloved creations, the Muppets, populated two smash-hit television programs -- the educational children's show Sesame Street (1970-present) and the syndicated variety show The Muppet Show (1976-1981) -- as well as a n...