So I just read P. M. S. Hacker taking apart the idea that there is something that it is like for a bat to be a bat (etc.) when I came across this on what it is like to be depressed. It seems very odd, partly because I think people are pretty good at latching feelings onto things. For instance, when I was in high school I worried a lot and could always find something to worry about: sometimes tests that were coming up, sometimes the fact that I wasn't worried about a test, which surely indicated that I had forgotten a test, etc. So I would expect a depressed person to be depressed about something, even if the cause of the depressed feeling was not that thing. Allie Brosh makes depression seem not like that. (I don't mean to suggest that she's wrong.)
(Speaking of consciousness, one level of it is sometimes said to be the kind that is involved when driving on autopilot. You're conscious enough to drive, but not actually aware of your actions and decisions. I wonder how anyone knows this isn't just a trick of memory. After all, no one ever knows that they are on autopilot, only that they seemingly have been. Anyway...)
Another thing that struck me about Brosh's essay is the last frame, in which she says that her "depression got so horrible that it actually broke through to the other side and became a sort of fear-proof exoskeleton." This reminds me of Wittgenstein's talk of the feeling of being absolutely safe in the Lecture on Ethics. He connects it with religion, rather than depression. Others might connect it with the feeling of being in love (perhaps), or other feelings or circumstances. What they have in common is the words used to express the feeling in question. This might not seem like enough, but I think Hacker does a good job of bringing out why it might be.