Just for the record, the C=Lowell Graphics Card and Macrosystems' RetinaZ2 cards also used segmented memory. In the case of the Lowell card, you can even use CybergraphX with it. :-)
Interestingly, the get the Lowell card to work with Cybergraphx you need to just like other graphics cards have enough Zorro2 memory space for the card's 1.5Mb of segemented graphics memory. There is some kind of trick involved to make the segmented memory work like other non-segmented graphics cards, has to do with how EGS worked iirc. There of course should have been a way to make the RetinaZ2 also work this way and there was supposedly a beta driver but I've never seen it.
