For me there is a difference between mail-art and art. Mail-art for me is a process, a concept. Sometimes it might result is something that is called Art. Some of the things I have produced (or have sent out) you can find on the site of www.artwanted.com and to be specific at this link:
http://www.artwanted.com/artist.cfm?ArtID=19335 (see my latest works).
Ruud