I had a math prof last semester that would walk around and clear the memory on all programable graphing calculators during exams.
lowsound
I had a number of professors who would do the same thing, not only to make sure students didn't have notes or formulas saved in the calculator's memory, but also to ensure students from a previous section of the class were not giving students of the current section answers to the exams via the calculator's memory banks.
Though apparently (at least in my circle of friends) I was the only one who knew that you can program in a whole semesters worth of notes into a graphing calculator (which every engineering student had, some even had 2 or 3).
Even if my professors didn't do this, I still wouldn't have bothered with cheating-via-TI-83; in the time it takes to go through and manually type in whatever concept or formula I was worried about remembering, I could just actually learn the material.