I added general project notes, links to relevant resources and a chronological log of projects.
The biggest benefits for me were:
* keep track of multiple projects;
* reduce overhead of switching between projects.
When the server hosting my wiki, err, disappeared, I decided to create a service that would provide me the benefits I'd found and also make them available to other developers.
Labradoc is the result:
* make general project notes with Markdown formatting;
* keep a chronological log of project progress.
Here's my own project list:
If you already keep a project log I encourage you to make more of it public (it's okay, the people that judge you badly for in-progress hacks you don't want to work with anyway :) ).
In either case, try out Labradoc and see how it suits your workflow.