SegaXtreme

I found, with the help of people of this forums, that:

http://www.smspower.org/smsreader/

It explains how to build a Sega Master System Cartdrige Reader / Writer, with the utility of dumping games and writing roms into the ReWritable Cartrige (how to create it is explained too, of course) to playing the roms into the console.

I want to ask if somebody knows the existance of another www with a similar thing for Genesis or Super Nintendo (the ReWritable Cartdrige I mean).

Thanks