My brother- being far more up to the minute on electronic stuff due to teenagers in the house- hooked my Mum up with a Wii set. Paddles for playing tennis against me, and a Wii fitness board, where she can do balance exercises (the stroke has affectd her balance) and things like these step-ups.
I came in to grab something and found Mum still going after more than an hour, quietly doing exercises all by herself, pushing herself to physically improve (which she is).
It reminded me of some of the first NIKE "JUST DO IT" commercials so I snuck back for the camera.
She does a set on the new weight machine three times a week as well...