Ruby Toolbox - Explore and compare open source Ruby libraries
HackADay - Hackaday.io is a platform for people who like to build things.
AlternativeTo - AlternativeTo lets you find apps and software for Windows, Mac, Linux, iPhone, iPad, Android, Android Tablets, Web Apps, Online, Windows Tablets and more by recommending alternatives to apps you already know.
Wikifactory - Engineer the future with Wikifactory. Wikifactory unifies teams in real-time, enabling efficient communication, streamlined workflows, and accelerated time-to-market.
UserBit - A full-stack qualitative research platform for UX & product teams.
Hackster - Hackster is a community dedicated to learning hardware.