If you have 15-20 minutes try this workout. I have been super swamped with homework, housework and the kids. I wanted a quick workout this morning that would (hopefully) torch a bunch of calories. I came up with a 500 Rep Workout. Do 10 reps of each of the exercises and repeat 5 times through. You can also make this a 1000, 1500 or even 2000 rep workout by just upping the number of times you repeat the exercises.
Let me know how long it takes you! Can you do it in under 15 minutes?