LyX is a fully fuctional WYSIWYM (what you see is what you mean) frontend for LaTeX wnich allows users with no programming knowledge to get the full benefits of LaTeX. It differs from products such as TeTeX as one needs to know no code and can simply write and mark any text as a footnote of chapter heading etc., and then hit the PDF button to get a perfectly formatted output.
Free open source TeX/LaTeX-Aware spelling checker.
A powerful application that allows users to edit TeX files.
Word processor that can check your mathematical reasoning.
Parses common ANSI codes to remove or convert them to another colored text.
Free and simple to use Finder Toolbar Script.