Kinto : Kinto is a lightweight JSON storage service with synchronisation and sharing abilities.
shadcn-ui : A set of beautifully-designed, accessible components and a code distribution platform. Works with your favorite frameworks. Open Source. Open Code.
bosh : BOSH is an open source tool for release engineering, deployment, lifecycle management, and monitoring of distributed systems.
Luckysheet : Luckysheet is an online spreadsheet like excel that is powerful, simple to configure, and completely open source.
CryptoZombies is a free, open source, interactive code school that teaches you to build games on Ethereum. The course is designed for beginners to Solidity and starts off with the absolute basics.