The original preprint system was scientists sharing photocopies

"The movement to make biology papers freely available before they have been peer-reviewed, let alone published in a reputable journal, finally succeeded in 2013, when bioRxiv (pronounced bio-archive) was launched by Cold Spring Harbor Laboratory. But 50 years before, the National Institutes of Health tried something similar: distributing unpublished scientific papers, or preprints, to a handpicked group of leading researchers."