Extract LaTeX from PDFs or handwritten notes in seconds just by taking a screenshot.

Download Snip for desktop and start saving time.

Free for 50 snips/month, $4.99/month for unlimited personal version.

Found via https://github.com/jethrokuan/mathpix.el, an Emacs interface to Mathpix.

Recommended by Wilfrid Hughes
http://www.wilfred.me.uk/blog/2009/12/05/notes-on-latex/

Overleaf is a collaborative writing and publishing system that makes the whole process of producing academic papers much quicker for both authors and publishers.

Overleaf is a free service that lets you create, edit and share your scientific ideas easily online using LaTeX, a comprehensive and powerful tool for scientific writing.

On-line handwriting recognition for mathematical formulas, generates LaTeX and MathML and can pass on the formula to Wolfram Alpha.

MathJaxTM is an open source, Ajax-based math display solution designed with a goal of consolidating advances in many web technologies in a single definitive math-on-the-web platform supporting all major browsers.

Intriguing collection of examples demonstrating pictures created using PGF and TikZ tools.

Muse allows to write documents using a wiki-like markup and to publish to a number of formats, including HTML, texinfo and LaTeX.

Good collection of tips for electronic (LaTeX) documents, revision control, PDF.