3 Pullup Ladders:
By yourself or with a partner, go to a pull-up bar. Do one, get down. While your partner does one, you rest. Do two. While your partner does two, you rest. Do three, and so on, till you hit failure. That's one ladder. Start over at one rep, and keep going till you've done three ladders.
3 Pushup Ladders:
The same as above, but with pushups, and do equal reps of full body crunches between sets.