Vim - IDE
I love coding. A friend at university first introduced me to Vim. I was already using Linux, but my editor of choice was nano, and Vim felt almost hostile at first.
Years later, another friend spoke very highly of Vim and I decided to learn it properly. It was painful at first. I was slow, frustrated, and constantly checking the documentation.
Most of the frustration came from my drive to make it do more and more. I spent a lot of time learning Vimscript, adding plugins and scripts, and eventually turning Vim into an IDE that I still use today.
Coupled with tmux, shell scripts, Python, and NERDTree, Vim became a very powerful personal development environment.