Digital Adventures [Official site]
"Online adventures and more for the digital desktop!"

Mapventures [Official site]
"Fantasy Adventures & Maps E-Books & Fantasy Grounds Modules"

• Adventure: The Oath of Kortis
• Adventure: Tower of the Past (Upcoming)
• Adventure: Den of the Fox (Upcoming)

White Haired Man [Official site]

• Adventure: Well Met in Kith'takharos
• Adventure: Well Met in Kith'takharos (incl. PDF)
• Adventure: The Missing Harvesters
• Adventure: The Missing Harvesters (incl. PDF)
• Campaign setting: Kith'takharos

FG D&D 4E Wiki (including download of ruleset) [Official site]
"Play the most popular role-playing game today!"

• D&D 4.0 Ruleset
• Manual, release notes, wish list, links

Four Ugly Monsters [Official site]
"Fulfilling all Your Fantasy Grounds Needs!"

• FUM Freebies and Community Created Downloads
• Map Pack: The Wilderness
• Map Pack: Deserts
• Map Pack: Mountains
• Map Pack: Buildings
• Map Pack: Generic Buildings (old-Style)
• Token Pack: Characters
• Token Pack: Kobolds/Goblins
• Token Pack: Orcs, Ogres, and Trolls
• Token Pack: Were-Creatures
• Token Pack: DM Essentials 1
• Token Pack: Familiars and Summons
• Token Pack: Samurai and Shinobi
• Token Pack: Wet Cavern Pack
• Token Pack: The Camp
• Token Pack: Townsfolk
• Token Pack: Basic Undead
• Token Pack: Dark Lair

CC2 Map Library [Official site]
"Community Map Collection & CC2 Artwork"

• Maps for every need
• Token packs

FG Wiki [Official site]

• FAQ, Advice
• Modifications, extensions, scripts
• Ruleset list

d5 [Official site]
"For all your ballad and saga needs"

• Quality materials for independent roleplaying gamers
• Articles, campaign worlds, modules, minis, ...
• European folklore