I've noticing that lately on Fridays I've tended to gravitate towards working on documentation, mostly because I'm tired and checking that some docs are up to date is easier than, say, debugging stuff that is not working.
However, the more I think about it the more I start to believe that it's actually a good thing, so the only thing that is missing before this can become A Thing is a fancy alliterative name: anybody has ideas? :D