The Startup Way - The new book from Eric Ries, author of The Lean Startup
UI Playbook - The documented collection of UI components
GrowthHackList - 100+ curated growth hacks for makers + early stage startups
UserInterface.io - Weekly UI/UX tips in your inbox for free
50 UI Tips - Improve your UI/UX skills in an hour, for free
Gainy - Stock market portfolio