Just last night on IRC I was commenting on the stinkeye I received at a company once when I suggested their tagging functionality mimic Stack Overflow's. Even though their product was a multiuser version of something that had existed at 1:1 scale for a decade, never did I hear it described in terms of what already existed. Based on more than this one example, I am convinced that there is a beautiful-farts narcissism in startups today where everybody thinks they're doing something new when they're really just making a drag-and-drop Megaupload, in-browser Sublime Text, Flickr-with-animation, or whatever.