That's probably obvious for many Photoshop experts, but even though I use Photoshop daily, I didn't know that was in there. It is probably because I don't take the time to learn Photoshop, I use it for what I need to do and I look for the features when I need them. I was doing some rotoscoping today and I absolutely needed to put points outside of the canvas. In the past, I just unzoomed to add those points, but I really had to be zoomed in this time and it is just not possible in the default way Photoshop works. What I have discovered is that it is easy to do this in full screen mode. To toggle between the modes, including full screen, you just have to press "F".