And QNX before that. But, that's a well-engineered, UNIX-like microkernel rather than Linux. Oh well...

QNX was open source for a while, what is surprising is that there doesnt appear to be an easily searcable version of the code available on google.

That was a bait and switch by management that I could tell. They got a bunch of contributions from the community then pulled it. Or just felt that it wasn't worthwhile after little contributions. I can't be sure.

Nonetheless, underlying technology is solid with that showing in Blackberry Playbook.

I regret not downloading the source code while it was available.

I lost my copy. Regrets here, too. Minix 3 is fortunately coming along nicely and already resilient against driver faults.

Yeah, I was a fan of QNX for some time. A complete functioning OS with X windows system on a 1.44M 3.5" disk.