https://bundleofholding.com/presents/OSCool

We provide each ebook complete in .PDF (Portable Document Format). Like all Bundle of Holding titles, these books have NO DRM (Digital Restrictions Management), and our customers are entitled to move them freely among all their devices.
Ten percent of each purchase (after gateway fees) goes to this offer's pandemic-related charity, Direct Relief. Direct Relief gets protective gear and critical care medications to health workers, with emergency deliveries to medical facilities across the US and to regional response agencies across the world.
The total retail value of the titles in this offer is US$89.50. Customers who pay just US$7.95 get all five titles in our Starter Collection (retail value $33) as DRM-free .PDF ebooks, including Vagabonds of Dyfed (retail price $8), Ben Dutter's unholy union of OSR ideals with Powered by the Apocalypse mechanics; Pariah (retail $7), Sofinho's psychedelic proto-Neolithic animist Old-School zine; Diego Nogueira's rules-light sword-and-sorcery game Sharp Swords & Sinister Spells (retail $3.50), plus its Addendum rules expansion that's twice as long as the corebook (retail $4.50); and the Iron Age comics-inspired street vigilante game Fallen Justice (retail $10).
Those who pay more than the threshold (average) price, which is set at $17.95 to start, also get our entire Bonus Collection with seven more titles worth an additional $56.50, including the hyper-stylized science-fantasy RPG Hypertellurians (retail $15); the Vagabonds location guide Dortoka: City on the Sea of Glass (retail price $8); Solar Blades & Cosmic Spells (retail $15), plus its campaign-changing adventure The Egyptian Situation From Outer Time (retail $5); and the modern urban-fantasy horror RPG Dark Streets & Darker Secrets (retail $10), with its GM Screen (retail $2) and its anarcho-punk vampire supplement Streets of Blood (retail $1.50)."
I don't think that there's actually anything here that screams "I want this" to me, but it looks like there's an interesting range of genres. Several different rules systems are used, if you don't already own them it might be worth checking how much work you will need to do to adapt this stuff for your preferred game.