Panerai did in 1999 with the WWF concerning the Mediterranean Sea. Panerai came out with a reference PAM 037 (just like a PAM 001, L dial) that had signatures of famous Italian celebrities on the caseback. Each individual watch had two duplicates, one to be auctioned and one to be retained by the celeb. The book is actually an artistic photography book, where on each page the celeb is pictured wearing the watch. The book was available as a free gift at boutiques and ADs.
BTW, one of the watches bears the signature of Maria Panerai.
Cheers,
Asi