Startup School - How to start a startup, by Y Combinator
Electron - Build cross platform desktop apps with web technologies
The Y Combinator Database - The definitive database of YC companies with all the metrics
Tuemilio - Email forms and referral waiting lists for indie makers
Apply to YC (Y Combinator) - Curated collection of resources for founders applying to YC.
JumpStart Toolkit - A pack of tools and goodies to jumpstart your startup