Figured I may throw out an AB work out suggestion. First off, this is for people who wish to strengthen each part of their abdominals in one basic excercise, and I warn you, its not for those of you with weaker abs. I can do about 80 or more sit ups but this absolutly rips my abs. It's called 5 minute abs, 1 minute per excercise but I wont lie, I can only do each excercise for 40 seconds, so I call mine 3:20 abs.

The point of this is to do each excercise for 1 minute, and then switch to the next right away, thus giving yourself a full 5 minute ab workout.
Ex 1. Lie with your back on the floor, straighten your legs, and begin lifting them about a foot to a foot and a half off the ground, almost like your walking but with your back on the ground. Don't let your feet touch the ground, they should come as far down as possible without touching the ground. As one foot goes down, the other shoudl be going up. Do that for one minute.
Ex 2. Put your legs straight into the air, and begin lifting your butt off the ground. It'll feel uncomfortable at first but you'll get used to it. This works your high abs. Make sure not to put your hans under your hips for support. Do that for one minute.
Ex 3. Crunches. Yup, just do crunches for one minute. NOT SIT UPS....crunches.
Ex 4. Straighten both legs out, keeping them off the ground and together. Bring them into your chest, or as far into your body as you can, and then straighten them out again. Like excercise 1, make sure not to let your feet touch the ground, and keep them straight. Do for one minute.
Ex. 5. Straighten your legs up into the air again , but this time bring them down to one side of your body, like your twisting yourself on the way down almost. Then to the other side, and back and forth you go. Do for one minute.
Now feel the burn. I normally try to do one set using 40 second intervals, and a second one doing 30 seconds intervals. Trust me, you WILL feel the burn.