Newegg offers four Fujitsu AA Ni-MH Pre-Charged Rechargeable Battery 4-Packs (16 batteries total), model no. HR-3UTCEX(4B), for $25.99 with free shipping. That's $1.62 per battery, $6 off list, and the lowest total price we could find. (For further comparison, we saw eight batteries for $14 in July.) These batteries can purportedly be charged up to 2,100 times.