Showed Garry's Mod off to JC and he seemed to find the structural posibilities in the environment. We even made a very quick truss element and played around with seeing how some of the rules work. For example objects only seem to take impact damage, not simply load damage - this would have an impact on its use for his needs.
He freely admitted it was a far more enjoyable and engaging environment that any of the other structures tools he had for the students.
[some random pics from the net of some of the structures type stuff that could be done]
Russell got both UT2004 and HL2/GMod working on the Dell workstations going into their 4th year - that is pretty good longevity it seems.
[journeytime = 0.5 hours]