The 100 MHz 6502!

Very neat development!

I can see how this would be more difficult for c64, perhaps difficult for c128 as they try to catch IO stuff for timing behavior.

If we can dream here:
What I would love to see is firmware for U2 or a c128-chameleon that pretends to be a fake soft-z80 running 1 instruction per 2 cycles. Sounds like a very small improvement, but instead would be possible in the crazy timing constraints and bus-wizardry a c128 has