The ADAPTIVE Communication Environment (ACE) is an object-oriented
(OO) toolkit that implements fundamental design patterns for
communication software.  ACE provides a rich set of reusable C++
wrappers and frameworks that perform common communication software
tasks across a range of OS platforms.

TAO is a freely available, open-source implementation of a
CORBA 2.x-compliant ORB that supports real-time extensions.

WWW: http://www.cs.wustl.edu/~schmidt/ACE.html
     http://www.cs.wustl.edu/~schmidt/TAO.html