I recently picked up this finisher from Dan John speaking on the Fitcast Episode 200.
It's pretty nice and simple:
8 one-arm kettlebell cleans
5 front squats w/one kettlebell held in the rack (i.e. against the chest with one arm)
5 one-arm kettlebell cleans
3 front squats
3 one-arm kettlebell cleans
1 front squat
You do 8/5 for one arm, then switch for 8/5 on the other arm, then 5/3, then 5/3, then 3/1 and 3/1. It's short and effective in getting your heart rate up, you can go pretty heavy (as Dan John says) because the clean allows for a lot of weight, and you get some good squat practice in.
I've used it with one of my clients recently, who ironically only has one working arm, so we couldn't switch up. We did the countdown straight through and then rested a minute to do it again. It was excellent. It's both harder than it sounds and easy to do. The strength element - you can use a heavy KB - is present front-and-center, too.
Give it a try!