I am a formal professional. When I am not shooting or writing, I am using photoshop… or sleeping, sometimes. But I usually dream about photoshop, so does that count?
Anyway, I have used every tool, on more then one occasion, except the measure command. That seems to do nothing but lag my computer and cause the program to crash, (and yes, I have tried it with two versions and one four machines, it is probably something wrong with the mac version, or I am just using it completely wrong.) I do everything from photo restoration (which, most of the time, involves MANY of the functions in PS) all the way to simple logos and business cards. I personally use most of the CS suite, being a small studio, I have to use and understand most of the what Adobe products do, but Photoshop and Illustrator are my two strong suites.
So, to answer your question: I know Photoshop better then I know myself or my family, and friends, combined.