The Daddy of the modern computer chip: Zilog Z80 CPU
The Z80 formed the basis for the personal computer revolution from 1976 well into the mid to late '80s. Such classic units as the ZX Spectrum and Amstrad CPC were powered by the Z80. A testiment to it's design is the fact that it's still being used in embedded applications today.
CPU-World: Zilog Z80 CPU
By way of a link to the previous post, the Sega Dreamcast VMU was powered by a shrunk down Z80 CPU!