latex4technics - Online LaTeX editor with autocompletion, highlighting and 400 math symbols.
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…
Hostmath - Hostmath is a user-friendly mathematical symbol or equation editor that provides you an opportunity to edit your entire difficult equation in seconds.
MathCast - MathCast is an equation editor, an application that allows you to input mathematical equations.
Lagrida Latexeditor - Lagrida Latexeditor is an all-in-one website that lets you edit, write or check the authentication of your mathematical equations or symbols in a decent manner without any hassle.
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.