PublicAPIs - Explore the largest API directory in the galaxy
Wicked PDF - PDF generator (from HTML) plugin for Ruby on Rails
The Unsplash API - No-limits, do-what-you-want API for access to 200K+ HD pics.
SEOBOTS.io - Easy to use bots for data mining and growth hacking: parsers, crawlers and much more.
API List - A collective list of APIs. Build something.
TexAu - Growth automation to scale your business faster