Looking through here, haven't seen anyone using Pandoc, so I'll through that in the mix. Offers the ability to write simple LaTeX intertwined with Markdown. I've been using it for everything from letters to homework assignments, seems to get the job done for most scenarios. Probably wouldn't use it for an extensive paper though. But it's nice to be able to start typing in Markdown, call `pandoc -o output.pdf source.md` and just have something nice to send out without a ton of setup.