If there is one operating system that has a special place in my heart, it's QNX. This microkernel operating system served as my main desktop operating system for months and months back in the day, during the short-lived QNX Desktop scene - which died out due to a lack of interest from QNX' parent company, QNX Software Systems. The money is in the embedded and high reliability markets, and that's where QSS - understandably - focused its efforts. QNX was sort-of open sourced in September 2007, and today the company has announced the release of QNX 6.4, the first major release since 6.3 in 2004.
Source : http://www.osnews.com/