This is the souped-up Speccy project I was taling about in teh Amiga Development thread... Isn't it great?
By the way, the Commodore One has a similar approach to some of its functions. There is a chip that loads up teh set of registers it needs to use. Since it has the souped up 6502, it might be possible to turn it into an Apple IIGS clone, for example.
Let's keep in mind thsi Sprinter machne would only be allowed to mimic other Z80 machines, I presume. Not like it can suddenly become a Commodore 64 :P