With the price of the chip being so low and it already having the I/O I dont see the need for a straight microprocessor.
I guess a better question would be if there are any 8-bit microcontrollers with the ability to add addressable memory, and/or were Princeton architecture vs. Harvard...?
That is a draw about an 8-bit CPU; the fact that you can add a whole mess of memory to it, and you aren't limited in how much memory you have for programs -or- variables (plus you get the fun stuff like potentially self-modifying code and such - in other words, more bugs!).
The bad part, though, is the fact that they are real CPUs, so you need to add your own MMU scheme, address decoding, mapping things into address space, etc - the chip count and the size of your PCB goes up fast (unless you can find somebody making SMT knockoffs of the popular 8-bit CPUs - doubt it).
At a certain point, I guess you just have to "graduate" and move on to ARM or some other architecture (Nano-ITX?)...
