I don't remember who said it, but I recall
someone(tm) (Bob Russell?) once
observing that the 1541 disk drive was the best computer Commodore ever made.
Surely that should be said about something like the 8050, which had a
pair of 6502s inside, with shared memeory (its used the trick that the
6502 onlt accesses memeory druing one state of the clock line, so by
inverting the clock signal to one of the procerssors, they can trivially
share memeory.
-tony