Jellifin - Trade commission-free stocks, ETFs and options.
Startup School - How to start a startup, by Y Combinator
Robinhood - Free stock trading service.
YC World - Explore Y Combinator companies by country
Naga - Join our stock & crypto trading social network with over 1 million users. Copy other traders fully automatically with a free account and over 1,000 tradable assets.
Y Combinator Companies - Interactive list of all 1000+ YC companies