If you've got 10 minutes, you've got enough time for this great plyometrics workout. It's a challenging mix of cardio and strength moves, using just your body weight. I've noticed that plyometrics really help me with my running speed and strength. This is a great fat-burner too. Prepare to get your heart pumping and the sweat dripping.
Do the following exercises for 1 minute each. Repeat the circuit twice.
Jumping jacks (Just like you did in grade school gym class)
Foot fire (Also called football drills--in a slight squat, with legs shoulder width apart, run in place, moving our feet as fast as you can)
Mountain climber (In push-up position, pull one knee in at a time, towards your chest, alternating legs as quickly as possible)
High knee (Run in place, lifting your knees as high as possible)
Burpee (Start in standing position, squat down, placing your hands on the floor in front of you. Jump both feet back, jump them back in, and jump up into the air to return to start. Repeat as many times as possible.)