I see folks fall into the same hole over and over again in my Acrobat training travels. They are zooming in on a page, and forget to drop the Zoom Tool when they're done using it. Each successive click to adjust the view only zooms them in more and more, eventually leaving them looking at a white part of the page. They are zoomed in to 6400%, and they are lost.
Because of this, I consider the Zoom keyboard shortcuts in Acrobat 9 to be some of the most useful in the program, and will allow the lost to be found instantly. Here they are:
The next time you find yourself lost on a PDF page due to a 'zoom mishap,' don't panic. Pressing [Ctrl]  zooms you back out to the whole page to regain your bearings.Once you get used to using these shortcuts, you may find yourself rarely reaching for the Zoom Tool with your mouse. Over the years, I have slowly changed from an occasional keyboard shortcut user to an avid, and almost constant one.
Do you love shortcuts? I talk about them and other productivity boosting techniques in my online Acrobat classes. I'm hoping to "meet" some of you in the classroom.