Inkscape - Inkscape is a free, open source professional vector graphics editor for Windows, Mac OS X and Linux.
Snipper.ml - A simple snippet manager in the menubar
LaTeXDraw - LaTeXDraw is a graphical drawing editor for LaTeX.
Snipline - Command-line snippet organiser for power users
Ipe - Ipe is a drawing editor for creating figures in PDF or (encapsulated) Postscript format.
PasteCloud - Store pieces of text or code and share it with everyone.