This is a brief list of recommendations for authors of scientific papers who make their work available online. It focuses in particular on producing high-quality PDF files with LaTeX and covers some other technical and typographic pitfalls.
Use beautifully rendered LaTeX math in chat.Just enter a room name and start chatting.Send your friends the URL after you create a room to invite them.
I recently found this blog which shows a business card with a QR card. I thought I'd create a business card with LaTeX with a similar QR code. I took a LaTeX template from here, found out about the pst-barcode pacakge, learnt the MECARD format, and combined them to make this: