Offset loading - whether using a barbell or DBs/KBs is an effective way to challenge yourself using the same old movements that are already in your arsenal.
In this case, I grabbed a 50lb KB and 100lb KB...
[YouTube=http://www.youtube.com/watch?v=y7vECNEzXSc&feature=youtu.be]
Things to keep in mind:
* Anti rotation - I'm moving as if I had the same weight in both hands. If you start favoring one side then you might be going too heavy, lighten up or decrease the difference in the two weights (75 and 50 for example).
* Brace hard on both sides to achieve balance and focus on moving the lighter side with intention.
* These can be a great rehab tool or conditioning tool - try going for time instead of reps at the end of a training session.