Also, while I was never a fan of RuneQuest, they put up one of the first adventures for it, Apple Lane
BF1 Tower of Skulls - This is a high level (10th-12th) Swords & Wizardry adventure, the first in a series. Seems to be a fairly interesting dungeon crawl based on the blurb. 48 pages, $6
inside this insidious site are the pits and perils of the imprisoned Demon Lord of Graveyards, where you will find among its rooms and levels ...
... a frost giant zombie covered in brown mold ready to strike down intruders ...
... bone golems ready to tip hanging cauldrons of dangerous liquid onto opponents ...
... a domed chamber filled with blowing snow, yetis, and an undead druid ...
... a garden of unusually magical and potent berries guarded by shambling graveyards ...
... a titanic mushroom beneath which dance demonic mushroom men spreading their vile disease ..
Redmark Adventures Volume 1: Varria - This is not a PDF, but a print product. $25 for a 40 pages. Has 10 2 page adventures and other stuff.
Beyond the Wall - Heroes Young and Old - More character options for one of the best OSR games. PWYW
Leprechauns for Basic Era Games - For B/X and its ilk. I think there was one of these in PC1 Tall Tales of the Wee Folk. But it's PWYW.
Leprechauns - Like above, but meant specifically for The Hero's Journey game. PWYW
Microlite75 Extended - PWYW
The Black Hack - 19 pages, $2
The Druid for Delving Deeper and OSR Games - One of the things I've never understood about White Box and its brethern like Delving Deeper is why play it if you are going to add in all the other non-White Box stuff, like Greyhawk/Blackmoor? Just use Greyhawk/Blackmoor. But if you do understand that, here you go. 8 pages, PWYW
Dyson's Cartographic Bundle - I've never liked his mapping style, I've found it very hard to use in games. But if you do, here you go. $20 for a ton of his stuff.