Someone earlier was looking for a way to charge K10D/K20D batteries without the official charger and I think the thread went nowhere. I can't find it now so I thought I would create a new one.
Energizer announced some new products in their Energi To Go line and one that would be of particular interest to us that have cameras that use proprietary batteries. Here is a link to an article describing and picturing the new devices:
Energizer Unveils Energi To Go Line - Gearlog
Wow, USB charging of your LiIon 7.4 volt packs. I will definitely get one when they become available.