I'm actually immensely tired right now. I might play a bit of a point-and-click adventure (Cognition perhaps).
A while ago, when I was sick and tired, I played a hidden object game ("Elizabeth Find"). Those usually bore me immensely when I'm fully operational, but my mind was working at 30% capacity at most, and in that state the game was okay (the dialogue was actually fun).
Trouble is, I don't think I'll be able to focus on the screen for long at the moment. So if playing "Cognition" doesn't work, I may just head over to librivox.org, and get myself a nice bedtime story. I think there are some works of Poe or Lovecraft that I haven't heard yet.
What would be nice, actually, for the state I'm in right now, is a game that's basically an audiobook version of one of those old "Choose your own adventure" books. As a computer game (purely vocal, no display), and ideally controlled controlled exclusively with the mouse, so that I don't have to move my hand ("If you want to kiss the beautiful zombie, click once. If you want to run away, click twice. And so on.)
But I don't think such a game exists. So, Cognition it is ...