I am a licensed radio amateur ("ham") with the call sign DJ5CW (formerly DJ1YFK). I love Morse Code (CW), especially at high speeds. To foster its usage and to preserve it for the future, I developed Learn CW Online (lcwo.net), a web-based Morse course and practice tool with an active community of a few thousand users.
In the ham radio section of my website you'll find more information about my activities and some radio related, free software I've written over the years (LCWO, ebook2cw, qrq, YFKlog, CW RBN Club Spotter, ...).
During the first semesters of my studies of electrical engineering at Dresden University of Technology (2003 - 2005), I transcribed some lecture notes in LaTeX. Over a decade later, they are still used by many students. Everything is available as PDFs and LaTeX sources, licensed under the terms of the CC-BY license.