Tricep Dips.php
A tricep dip is sort of an upside-down push up, with your hands placed on an object and your feet on the floor, legs almost straight (just don't lock your knees) and the front of your body facing upward. Once you're in this position, simply drop down into your dip and push yourself back up. Keep pumping and enjoy that tricep burn!
Raising your feet by placing them on an object of similar height will increase the workload on your arms and therefore the effectiveness (and impact!) of the exercise.
Tricep dips: going all out
Taking things even further, you can use a set of horizontal bars about shoulder width apart to push yourself up. Now - with your full body weight resting on your arms in between the bars - do those same dips and feel yourself getting stronger with each rep. You wanna be a true ninja? Raise your legs so your body makes an L-shape while dipping.
One-armed tricep dips
And finally there's the one-armed variant: from starting position, extend one arm forward, extend your opposite leg forward, and drop down while supporting your body weight with your other arm and other leg. Now push yourself back up and do the other side. Pretty awesome, right?
Other ab exercices
Flutter Kicks
Hanging Leg Raises
Leg Raises
Russian Twists
Scissor Kicks
Sit Ups