I was one of 22 artists selected by Topps to do some "sketchagraph" cards, which are new inserts for Star Wars Galaxy 6 (very rare, from what I understand: 1 in every 135 packs) featuring an authentic signature from a Star Wars actor along with an original sketch by the artist.
The list of signers includes:
Mark Hamill (Luke Skywalker)
Carrie Fisher (Princess Leia)
Ray Park (Darth Maul)
Jake Lloyd (Episode 1 Anakin Skywalker)
Orli Shoshan (Shaak Ti)
Amy Allen (Aayla Secura)
Jon Berg (FX artist, cantina creature actor)
John Morton (Dack Ralter)
Mike Quinn (Puppeteer: Sy Snootles, Nien Nunb & more)
I did 2 of Mark Hamill's, 3 of Carrie Fisher's, and 5 of everyone else's (I think everyone had these same ratios). Basically Topps had the actors sign the cards in advance, then sent the cards to the artists.