HP Distributed Smalltalk
A version of Smalltalk created by the HP company in the early 90's, that featured a distributed CORBA based object system. Initial version ran on HP-UX and Microsoft Windows 3.x and featured a version of VisualWorks underneath, but after some input from IBM eas ported to SOM and made available for AIX and OS/2. Code is fully abstracted from the host OS so an application written for one host OS will be portable to others without any code change.
HP sold the system to ParkPlace-Digitalk in March 1996.
Links and publications
http://www.hpl.hp.com/hpjournal/95apr/apr95a11.pdf