How and when did we start using this? As English is not my native language, I find it funny that 'Fuck you.' is an insult. As opposed to wishing someone to have a wild night, wich is hardly insulting :).
Steven Pinker suggests it's derived from "(God) damn you", and morphed to "Fuck you" along with many other phrases when increased secularization made religious swearing lose its punch. As an English phrase, it's nongrammatical and as such not wishing someone anything.
source: Stuff of thought / or http://pinker.wjh.harvard.edu/books/stuff/media_articles/TNR%20Online%20%20What%20the%20F%20%281%20of%203%29%20%28print%29.htm