Note: Things I Learn from the Internet is a series of post containing snippets of wisdom collected from stuff I read on the WWW which do not warrant a post in itself.
HubSpot: A marketing software platform. Tools include SEO, web analytics, social media, blogs, etc
gun.io: marketplace for web development freelancers to find gigs.
Muck Rack: The easiest way to contact PR professionals, marketers and journalists using social media. Also allows journalists and bloggers to build free portfolio.