There is a great repo on GitHub of TILs. The author (jbranchaud) states:
A collection of concise write-ups on small things I learn day to day across a variety of languages and technologies. These are things that don’t really warrant a full blog post.
I think this is a pretty cool idea, but putting together the repo with the index can take time and interrupt your workflow. I wanted to make it very quick and easy to add TILs, so I wrote TIL-Tool. TIL-tool is a command line application invoked using til that makes it very easy to write TILs and generate an index.
To create a new TIL, run til open topic/title:
til open Python/list_comprehensions
This will open up a new text document which you can edit. Once you are done you can save the document and til. If you have configured a git remote (e.g. on GitHub), then you can then run til push which will build an index and push changes.
All TILs are stored in ~/.til