Up until 3 months ago I wouldn't buy a digital camera unless it ran on AA batteries...so I had more than a few around...some as old as 6 or 7 years old.

I think I'm going to buy some MAHA Imedion ultra low discharge batteries. I hear they're some of the most cold resistant NiMH batteries around. MAHA claims they perform at full capacity (or close to it) up to -10C.