QZAP - Queer Zine Archive
Queer Zine Archive Project has just celebrated 20 years of truly fantastic work preserving the history of queer zines (zine = small self-published magazines). They have zines going all the way back to the 70s!
Lesbian Herstory Archives
The Lesbian Herstory Archive has existed for over 50(!) years. They are fully trans inclusive, and honestly an incredible resource. You can visit in person (with appointment, NYC USA), or check their digital collections