About a year ago I bought this semi high-tech NiMH battery charger:
The main attraction was the "refresh" feature. When you set it to "refresh", it drains the battery, then charges it, and measures the amount of charge. Then it drains the battery again, charges, measures, etc. over and over until the amount of charge is no longer growing. This can take up to a week, but it really does quite a good job of getting the batteries close to their original capacity. So whenever my batteries don't seem to be holding as much as they used to (which isn't real often), I'll put them through a refresh cycle.
Then one day at work I took some old batteries to our battery recycling bucket, and I noticed that someone had discarded some rechargeable batteries. I took them home, put them through a refresh cycle, and voila, they work fine now. Over the last few months I have been checking the battery bucket regularly and now have more batteries than I will ever need.
Of course there are a few that are not recoverable (i.e. will not take a charge), but that seems to only be about 10% of them.
Now you could say that if I were truly frugal I would not have any battery-powered gizmo's, but I'm not quite there yet, especially my kids. But in the meantime this charger is keeping me well-supplied.
I once worked with a gal who had several battery rechargers on her desk at work. She would bring all of the rechargeable batteries from home, and use her bosses electricity to charge them (I actually believe that she conned him into buying the chargers, even though the office used no batteries!)
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