Sometimes my head hurts from all the papers I have to read. All the lines of software I have to code. All the pages of high quality scientific output I have to write. All the people I have to impress.
At those times I'm a little whiner, a weak quiter, feel so sorry for myself, and blame it all on something stupid like: I must know what going on on Facebook, or in my GMail inbox. I think I need a cup of coffee, a walk, to go to the rest room, to air out, to take of my shirt, put my feet up, not enough blood in the head, or whatever. Whatever keeps me from working.
At those times I'll watch this video, just once, take a few deep breaths, exhale slowly, and then get to m*therf*cking work on that m*therf*cking Ph.D.