Since the 1970s, the San Diego Comic Con has held the Robert A. Heinlein Blood Drive. In 1989 they gave people who donated a small portfolio of printed plates by different comic book artists as a way of saying thank you. The plates were 5" x 8" and printed on glossy card stock and enclosed in a plain white envelope. Here's the plates from that portfolio. They're tough to find on the second hand market.
| Sergio Aragones |
| Jack Kirby & Michael Thibodeaux |
| Frank Springer |
| Alex Toth |
| Bill Woggon |
| Bil Keane |
| Mort Walker |