From the November 2005 issue of Game Developer Magazine, a couple of screenshots and mentions of Softimage XSI.
From the “Heads Up Display” section:
From the article “SCALING THE CABAL: VALVE’S DESIGN PROCESS FOR CREATING HALF-LIFE 2”:
eX-SI
ICE, scripting, and other tech stuff about Softimage aka XSI
eX-SI 