Comment IPython uses markdown (Score 1) 204
For those doing scientific programming, the IPython notebook is a joyful place for interactive exploration and can be appropriate for document creation. Notebook cells can have code, images, or text, and text can mix Markdown and LaTeX (rendered in the cell via MathJax). Notebooks can be converted to HTML or PDF (via LaTeX), using the nbconvert utility (which depends on pandoc). For serious document production, this is not even remotely a replacement for LaTeX, but it can be a great place for interactive work.