I've heard or seen the word 'gimcrack' a few times lately (it's in this article - "the gimcrack glamour of the London Olympics", and I think I heard writer Will Self use it on the radio), so perhaps it's getting a new lease of life.
It was originally, in Middle English, spelled with a b instead of an m, and the OED thinks that it may have a link to the Old French giber to shake. The m may have crept in because of an association with the obsolete word gim, meaning smart or spruce. Nowadays a gimcrack is a knick-knack or a useless ornament, something showy but unsubstantial; the OED thinks that the original meaning may have been 'slight or flimsy ornament'. In the 17th century it began to be used to refer to people, and meant a fop (who would certainly have been 'gim'). In the 18th century it was then applied to women, when it became more insulting and contemptuous.