i just found out that the sega genesis can be overclocked by cutting pin 15 on the 68000 processor and adding an external oscillator in any frequency you want from stock up to about 12 or 13 mhz. its said that 13 mhz is where stability takes a hit.
this mod totally eliminates slowdown in games.
you can add a switch inbetween the stock frequency and the overclocked one so that your sega cd will still work (it only works on the stock clock).
I just ordered some 11 mhz oscillators.
I finally got the oscillators in yesterday. I will be doing my first genesis overclock soon. So thats what they meant by blast processing. :P