Parallel port isolation

A while back there was a lot of discussion here about building a module
to isolate a PC parallel port. Did any thing ever come form that? I
recall someone was going to offer a board for this.

What I want is a little box to plug into the PC, maybe on a short cable
or direct into the back of the PC, and have screw terminals on it for me
to hookup to my driver board. Anyone build such a box.

ron