Stem_Cell said:
Well, one way to check for dupes is to search for the tags. Considering there are few pics on this site, some combination of tags will eventually tell you if the image is there or not, particularly tags which are very common (such as including eye and hair color in your search, as in "brown_hair blue_eyes collar", for example.
That only works assuming that all pics have been tagged thoroughly, and they haven't. I've gone back and tagged some of the old images, but there are still a LOT that are missing tags. =/