Photomosh - Turn anything into a vaporwave
Sitecake - Drag and drop CMS for HTML websites. It's flat file CMS so it's pretty fast.
MVGEN - Make your own music videos with audio, gifs, and special effects
Anchor CMS - Free and lightweight blogging system
HearSeeParty - Combine Gifs with with music using tags
Textpattern - Textpattern is an elegant content management system that is free, open source software.