Welcome to Capheinds Big Bad List of Roleplaying System Reference Documents, a gateway to open rule systems in a handy hyperlinked format. If you know of any I haven’t yet listed please let me know.

D20

Wizards of the Coasts Revised (v 3.5) D20 System Reference Document

The Hypertext D20 SRD (D&D 3rd Ed)

D20 Pathfinder RPG SRD

D20 Modern SRD

D20 Heros SRD (Mutants and Masterminds)

OSR

Labyrinth Lord SRD

Swords and Wizardry SRD

Dungeon World SRD

The Traveller SRD

Basic Role Playing

Renaissance SRD

FUDGE

Fudge SRD (Mirror)

Mudge, Mook’s Fudge (Hypertext rules, not specifically an SRD)

Jazz SRD

Icons SRD

Fate Roleplaying Game SRD (Core, Accelerated Edition, and Toolkit)

Spirit of the Century SRD

Diaspora SRD

Archmage

13th Age SRD

The Archmage Engine SRD

OTHER

Bulletproof Blues

OpenD6 SRD