Ab-Jab: Sit-up slant board with an inflatable boxing speed bag affixed above the knee area. Likes: Unique, challenging, skill-building workout that blasts your abs in a short period of time. Simply sit up and punch the speed bag 10 times, lie back down, and do it again. Punching works abs and obliques at once. Twenty-five reps left me wasted. Change the workout by simply touching forehead to bag. Dislikes: The back pad -- and the entire device -- is too short by 2 feet. On the downswing, it's difficult not to clunk your head on the bare floor. We had to put a pillow down to prevent a concussion. Also, tools are not included; you'll need two wrenches for assembly. Price: $149.95. (800) JUMP-USA; www.jumpusa.com/ab_jab.html.