Just googled for "High Functioning Depression" and three of the top four links were to my posts on Depressed Academics on the topic. (Though our overlords Google knew it was me searching so maybe they bias the results.) In a sense this is dispiriting: it would be better if there was lots of great information on the topic instead of these few posts.
This is the top link: a thread on reddit.
Something leapt out at me as a description of what high functioning depression can be like: "for example, I can work hard all day long, write complex documents, provide legal advice etc. then I come home and I am almost crying because I just cant face doing the dishes."
Also while I'm here, it might be worth mentioning the subreddit (if that phrase means something to you) /r/depression. It comes with a lot of caveats but does seem to be quite active.