This isn't the best way to do this, but it may save you some time. There is a program called remotely anywhere, which you can try out 100 licenses for 30 days (it installs remotely as well). Instead of walking around to each machine you could remotely access them and install the software that way. ie you could put the messenger software going on one, log into another, and so on. If you like the software a site license is about $6400 dollars.....
Other than that, I am not sure of any free trials that will allow licensing to that many computers. I will watch this thread as I am interested now.
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