First it is always hard to loose a good friend and father, so my condolences go out to Slim's family and his friends.

I'm not a hardware hacker, but are there any commercial digital systems that support this kind of breadboarding?

Well, there are boards like these:

http://www.mouser.com/ProductDetail/Global-Specialties/PB-50...

http://www.erst.ch/english/virtex2/virtex2.html

http://www.mcustore.com/acatalog/AVR-Ready_Prototyping_Board...

Google "prototyping board" for more.

Thanks