here i am at work again, and i can tell you that in the cupboard here, i've got two adapters that allow serial devices to be plugged into a USB port. and we've got all sorts of adapters and stuff downstairs that we no longer use anymore since all the designers et c have got G4s and all the rest of us have G3s.
Come to think of it, our PowerPCs from a few years ago had a few i386 looking ports on the back...