Gym Ball
These are fantastic whenever you want to work on your stability. Sit up straight on the ball (about 1/2 way on) and tilt your pelvis back and forth. You can then progress up to rotating your pelvis from side to side and then a full circle. Try not to bear too much weight through your feet and control the movement from your stomach muscles instead. To make it safer, I would advise having someone sit next to you and do this exercise (if possible) on the carpet.
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