The idea of creating a documentation and/or readme files for your projects is nothing new, in many cases - it's essential, because without a good overview of what your program and/or software does: it becomes useless to 95% of the population! Have you ever avoided creating a documentation file?
I really like how GitHub is tackling this problem, for every GitHub project - there is an automatically generated README file (mind you, it's empty at first) that needs to be populated with information, such as code snippets and demo usage. Take a look at this demo.
It won't just improve your workflow, or productivity. Learning to create documentations (using accessible 3rd-party services) is going to have a great effect on how good you are as a programmer, and also deepen your understanding of whatever it is that you're working on. Right, lets take a look at our options.
Daux.io is an documentation generator that uses a simple folder structure and Markdown files to create custom documentation on the fly. It helps you create great looking documentation in a developer friendly way. It's totally Git friendly, and has some great features like Google Analytics integration, and it's totally built on Bootstrap, giving you that designing freedom!
The Documenter offers a way to generate documentations for authors of Envato marketplaces. I know a few developers and designers who're into building stuff for the greater population. It takes time to produce good documentation for Envato sites, so use this tool to take away those challenges. Building should be fun, and this tool will help it make so.