Hawaiian singer Israel Kamakawiwo'ole's fame has now made it to Wired (see the story here). The short article notes the continuing popularity of Bruddah Iz's version of "Somewhere Over the Rainbow/What a Wonderful World" on the iTunes site as well as making it to number one on Microsoft employee buying list on Amazon (Microsoft? - ed.).
Obviously, his type of music is not for everyone but many people, having heard this song, can't keep it out of their head (and hearts) and so are buying it from iTunes and Amazon.