django CMS - Enterprise Content Management with Django The open-source CMS used by thousands of websites since 2007
SketchCasts - A weekly screencast, all about how to use Sketch
Concrete CMS - Concrete CMS is an open source content management system for teams. A website builder with built in tools make editing content easy.
Base UI Sketch Framework - Huge set of everything you need to design and prototype
Kirby - Kirby is a website for businesses to use to sort contacts and other information. The site is easy to use and features several details for businesses of all sizes.
Remake - A way to make web apps with just HTML & CSS