I was daydreaming about these things last week though. Imagine if they added a C64 on a chip, some C64 game ports, maybe a SID chip, and a few other touches.
Ok, so this isn't *entirely* related, but it does involve a C64+SID-on-a-chip: http://www.picobay.com/projects/2007/01/picodore-64-commodore-64-pda.html
And it's in a Pandora-sized sort of format, so perhaps it does count, going by the rest of the thread...