The Farallon Etherwave was a nice little ISA networking card with *two* 10-BaseT ports. The idea was that you could chain them together without a hub. (But for the extra price they cost, you could probably get a nice hub :) What they're really useful for is a 3-computer home network, since the card acts like a hub, you just plug in the two computers into the Etherwave and go. It used (or was compatible with, I'm not sure) the 3c509 chip.