PublicAPIs - Explore the largest API directory in the galaxy
Lasso Content Curation - Become an information ninja. Stop losing the info you need.
API List - A collective list of APIs. Build something.
Pocket - When you find something you want to view later, put it in Pocket.
API for Product Managers - The A to Z of APIs for product managers
Pinboard - Pinboard is a personal archive for things you find online and don't want to forget.