My Favorite Mountain Climber Variations

If you're trying to get a workout in at home, mountain climbers are one of my top three favorite go-to movements. Especially if you're short on equipment but still want a great full-body exercise that will build muscular strength as well as build your cardio endurance.
They're awesome. They work just about every muscle in your body, simultaneously, and give your heart and lungs a run for their money.
Here are a few of my favorite variations so that you can mix things up, keep it fun, and keep getting awesome results.
WHAT'S YOUR FAVORITE BODYWEIGHT EXERCISE?