From the original thread on reddit, Apparently I don't look up enough when I play Deus Ex: Human Revolution because I missed some really unique ceilings.
The full list is here: http://imgur.com/a/FDAbV. Below are three that I particularly liked. Click on the images to see a larger version.
(Speaking of the topic of looking up, I did much more of that in Dishonored – which plays just like DE:HR – because Dishonored's “blink” ability will naturally start having you look for destinations to perch on well above your current position.)
