19: 1991 Donruss Elite Signature Series Ryne Sandberg

1991 was definitely still the junk wax era, and the junk wax had expanded with Topps, Donruss, Fleer, and Upper Deck all releasing products that year. That, coupled with a number of busts in recent years for prospectors (Brien Taylor and Todd Van Poppel come to mind) left a lot to be desired in the industry. Donruss had a set for a number of years in their product called Diamond Kings, with artistic renderings of star players on the card. In 1991 they introduced Elite Series, a chase insert set with a high gloss finish and gold edges. Cards were mostly numbered to 10k cards, which seems silly now, but was considered an insane short print then.
Out of that came a single card shorter print card. It was an autographed card of Ryne Sandberg. The concept was almost unprecedented, adding such a chase element to baseball cards. After that, inserts and autographs started to become synonymous with pack opening.

Random Ryne Sandberg Fact: Sandberg was drafted in the 20th round of the 1978 MLB draft. From everyone drafted in that round that year, they had a total of 8390 MLB at bats. Sandberg was responsible for 8385 of them.