Encelo's Projectz - OS Experiences

The QNX Real Time Os is based on a microkernel architecture (Neutrino).
I used it very little, I think it's powerful and promising, and I liked a lot the Photon interface.
I was really astonished to see what the single 1.44mb disk distribution could do when I first downloaded it, pretty cool.
I didn't like the fact it is a proprietary system and that the full SDK and other developer support is sold instead of being available for free.