Kettle Bells are a definite move in the right direction. I have a set of kettle bell handles from IronMind, as well as, a set similar to DragonDoor's. The regular non-adjustable kettle bells work much better. I also have a Brown Bear Pack Weight which is a packable kettle bell. The Pack Weight is an excellent kettle bell with the flexibility needed for deployments. The other advantage to the Pack Weight is that the shipping cost is drastically minimised. It is also something a rigger should be able to easily rig up.
Brown Bear Pack Weight:
http://www.packweight.com/index.htm
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