Inkscape - Inkscape is a free, open source professional vector graphics editor for Windows, Mac OS X and Linux.
MathType - The Professional version of Equation Editor- MathType is a powerful interactive tool for Windows and Macintosh that lets you create mathematical notation for word processing, web pages, desktop publishing, presentations, and for TeX, LaTeX, and Math…
LaTeXDraw - LaTeXDraw is a graphical drawing editor for LaTeX.
Math Magic - MathMagic Equation Editor for Desktop Publishing software & Word Processors, Adobe InDesign, QuarkXPress, MS Word, iWork, for Technical writing with very easy interface and fast input.
Ipe - Ipe is a drawing editor for creating figures in PDF or (encapsulated) Postscript format.
MathCast - MathCast is an equation editor, an application that allows you to input mathematical equations.