ChorusOS
   Growing article, with links to many related topics. Wikipedia.
   http://en.wikipedia.org/wiki/ChorusOS

ChorusOS Open Source
   Microkernel OS used in realtime and embedded environments. Sun Microsystems open sourced it, with 4 licenses: Sun Public License Lite, GPL, Mozilla, FreeBSD. Description, download. [ExperimentalStuff.com]
   http://www.experimentalstuff.com/Technologies/ChorusOS/index.html

Micro Kernel Reference: ChorusOS
   Brief, dense technical summary of Sun Microsystems ChorusOS.
   http://www.crhc.uiuc.edu/~dstott/ukernels/chorus.html

Sun Announces ChorusOS 4.0 Software
   Cornerstone for new embedded telecom platform; combines power of Solaris with realtime performance of ChorusOS.
   http://www.sun.com/smi/Press/sunflash/9906/sunflash.990608.3.html

Sun Microsystems, Inc.
   Makes ChorusOS: highly scalable, reliable, POSIX compliant, embedded, realtime operating system; used by top telecom suppliers, in: public switches, PBXs, access networks, cross-connect switches, voice-mail systems, cellular base stations, cell-phones, we
   http://www.sun.com/chorusos/