b) Navigating in small spaces http://www.youtube.com/watch?v=63bxfweC5iE&feature=related

 So, I watched the video about navigating in small spaces and I had already used mouselook a lot, so this didn't end up being new information to me.

So here I am in a tight space.  Oh no!

No worries.  When I enter mouselook mode I can easily walk myself out without having to deal with the bizarre camera collisions that invariable occur in this situation.  See:

What I did not find though was the cool feature talked about in the video, where you could bring up the map of the world and teleport yourself quickly to another location.