I have a countless number of cameras and electronic devices lying around at home with an equal number of differing batteries. Some devices even came with no charger at all and use a dedicated power supply to charge the battery.
So, if you're travelling, your luggage is crammed with cables and chargers of which one usually turns out to be the wrong one and another missing.
Incidentally i found the almost perfect solution for this problem at a local dealer. It's called "Hähnel Unipal" - a charger with two freely adjustable contacts to fit any Li-Ion or Li-Po battery within the 3,6/7,2 Volt range. Plus, it offers an USB outlet to charge USB-powered devices and it can load AA & AAA batties. The only thing i'm missing is a CR123 charging option ;-)
A special tip: If you have problems with retracted contacts, just rotate the battery and charge it upright...