I use it when I need to write some documents (user guides etc...). If the alternative is open office or some other "WYSIWYG" editor I'll take LaTeX any time.

I don't really love it though, I find myself using org-mode more and more for that purpose, then I let emacs generate the latex code for my doc. It's not nearly as flexible but it works well and your source is a lot more readable.

I also use LaTeX for my resume, if you find a good theme they end up looking pretty sharp and professional with little work.