FontForge - Free (libre) font editor for Windows, Mac OS X and GNU+Linux
CKEditor - Real-time collaborative future-ready rich text editor
BirdFont - Birdfont is a free font editor which lets you create vector graphics and export TTF, OTF, EOT and...
Summernote - Summernote is a JavaScript library that helps users create WYSIWYG editors online.
FontCreator - This professional font editor allows you to create and edit TrueType and OpenType fonts.
Froala Editor - Froala Editor is a WYSIWYG HTML editor that enables rich text editing capabilities for the applications.