The "343": We all know what that number stands for. For many of us not a day goes by we don't think about it. It shaped the future for all of us. Now a workout to honor those fallen heroes.

For time: Intermediate
100 flights of stairs-OR-run two miles-take a break if needed
100 push-ups
100 squats or split up lunges with squats; as long as total reps are 100
43 burpees 

Intermediate Workout #2: 
Body weight exercises can be very effective. Here is a good one:
Push-ups: 20-40 (number will range depending on person/strength)
Plank: Hold for 30-60 seconds
Flutter Kicks: 50 total (25 kicks each leg)
Mountain climbers: 50
Repeat 4 times

Intermediate Workout #3; "The American":
This workout will push your mental fortitude and heart, but will be well worth it and you will feel like a damn good American Warrior when you're done:
Burpees: 25
Squats: 50
Jump-lunges: 20
Pushups: 25-30
Crunches: 25
Sprints: 5x's 20 meters
REPEAT 5 TIMES