In total there are 55 arcade cabinets, most of which are the upright Aero Cities cabinets, but it’s the game boards that they contain that’s the most exciting discovery."
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No, people who have tried SL and left unimpressed are making an judgement informed by their experience. To say that they had little clue about what goes on there simply means that Linden and the cabal of initiates in the know have done a piss poor job in exposing "what goes on there" in a simple, attractive and easy to use fashion.
The rest of your post was interesting - I hadn't thought of SL's possible uses by the disabled community.
"Let every man teach his son, teach his daughter, that labor is honorable." -- Robert G. Ingersoll