Traps & Trickery has such a feat...
and making it a feat seems to be the best way to go.
The Traps & Treickery book contains a feat - 'perfect memory' or 'instant memorize' I forget the name. Basically, you look at a doument, you can remember what it looks like, and reproduce it if need be. Reproduce the info, that is, forgery still needed to duplicate it exactly...
But that is about all there is to it.