We found the Ansmann booth down in hall E at NAMM - they were showing a range of smart recharagable batteries. Of particular interest to us as we take 40 AA Lithium Ion non rechargables to power our gear at the trade shows.
They do a couple of NiMH varaiants, the longer life but lower power maxE Pro - with around 2100 recharges, and the 2850mA H range whch give you around 300 charges. But the key thing is the price, at around only 30% more than disposables you can save big if you use a lot of batteries.
If you use a lot of batteries, its a no brainer.