Hey - thanks this is awesome advice. I've tried it today and actually enjoyed it. It's made it easier to get clarity on my thoughts and led to some useful ideas
Glad you enjoyed it :) I was actually looking for this video back when I posted this reply but couldn't find it. Just found it though ... this is a great talk at Google by Chade-Meng Tan, I highly encourage you to give it a watch:
http://www.youtube.com/watch?v=r8fcqrNO7so
In particular, the part about training for mindfulness has also been extremely helpful for me. I'm really starting to believe his assertion that learning to calm your mind can be trained. I tend to close my eyes and focus on breathing while I'm on the train after I finish the stream-of-consciousness exercise from above; this might sound silly, but I even notice that the muscles in my face are more relaxed after I do these things :)