50,000 units *is* quite a lot for a development board, actually. Many more than most companies could ever hope to sell, at least of a single model. If they could, they wouldn't be so damned expensive. What bulks did Castle make Iyonix boards in originally? Very small, I imagine, partially explaining the high price. Let's hope if the 50,000 unit thing does happen, the benefits will trickle through to the normal RISC OS people in the form of much cheaper machines.