When Shimano did the XT discs that had 4 piston calipers and braided stainless lines I'm pretty sure they had some 90° banjo fittings. They'd probably be pretty hard to find now since it's been more than 10 years since they were current, but you might have some luck.

I found it...like this?
http://www.bikepartsplace.com/discou...dware-sm-bh63/



The brakes were XT M755 if that helps.