Like many, I'm a fan of DiNotte bike lights. They're bright and durable. The Pro series uses ordinary AA batteries, and so can be powered with inexpensive rechargeable batteries. The only problem is prying the batteries out of the battery pack to recharge them.
Not any more. About a year ago, I built a couple of chargers that allow me (and my friends) to charge the battery packs without taking the batteries out. (It was Brian Pratt's idea, so props to Brian.)
I have put up a web page with complete instructions to build your own DiNotte battery pack charger. It's preposterously simple.