It's NOT a postage stamp. It's "metered mail," and therefore the "living person" rule does not apply.

There are already custom metered mail logos, and no one collects them. I think it would have to be 1) a celebrity of some sort and 2) a special occasion, like a wedding before they would have any value.

It would be a nice way for an artist to promote his or her work, but kind of pricy.

What I find interesting is that they are using human beings to screen each design. No nudity, nothing politically controversial, and no copyrighted material is allowed, and they don't want to risk anything slipping through.