it raises the issue of how to deal with the fact one may have breached whatever copyright pertains to the original image, especially in the absence of any model release or written permission to photomanipulate an image one has downloaded from a newsgroup or website. however, there is an small industry related to this (called celeb fakes), with its own newsgroup (in the alt.binaries hierarchy) and its own set of websites (all porno, hence I can't post a link. one guy (nick = lux luthor) even went so far as to create what he calls the "fake university", where one can get tips on how to do these photomanips to the point where they're no longer detectable. hence the creation of another site, the "fake detective", where a guy in support of celebrities' rights goes to great lengths to show how one can spot these photomanips.