Ruby Toolbox - Explore and compare open source Ruby libraries
Startup Stash - A curated directory of 400 resources & tools for startups
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.
Content Marketing Stack - A curated directory of content marketing resources
LibHunt - LibHunt tracks mentions of software libraries on relevant social networks. Based on that data, you can find the most popular projects and their alternatives.
StartupResources.io - Tightly curated lists of the best startup tools