Despite popular belief that MEIKO was the first Vocaloid, the first two were released by UK-based zero-g.  Leon, the male of the two, was released early in 2004, months before Crypton's MEIKO.  Leon doesn't have a character model to speak of outside of fanart, and his popularity was more in a Japanese market than an English one.  Basically obsolete, he tends to be used as backup for the other male Vocaloids.