If the La Crosse BC700 is too expensive for you at $30-40, take a look at this Sony Charger:
Unlike most chargers, the Sony charger is not a "dumb" timer-based charger, so it won't overcharge an already full battery. The Sony also handles each cell individually, which is rare in chargers of this price range.
Have a look at this review for more info: http://www.amazon.com/review/R1D2Q4UHFLEWSI
I paid $10 for mine, but even at the current price of $14, it's a pretty good deal. (and it comes with 2 low-discharge AA batteries, though they are only 1000 mAH).
This is a good one. If Imay, I suggest this one: http://www.amazon.com/gp/product/...UTF8&psc=1
It has refresh function, which is what I felt like the missing feature in the smart charger. Also, this one comes with 4 2000 mAh batteries. So it makes it a good deal.