Craziest things I've seen at a garage while waiting for servicing have all been at our Lexus garage. For a while, they had used Lamborghinis in their showroom. And that Lexus dealership is huge and has a very elegant, multiple part showroom . Check this shit out
http://www.mcgrathlex.com/dealershipphotos
I get lose in their sometimes.
Anyway, I saw a bright-red LF-A they had waiting to be serviced in the work area. Or maybe someone just got it delivered and they were doing some point inspections before they picked it up. But the mechanic started it up and revved it a few times and inside the garage is was basically like being in a tunnel with the revs.