This deal has ended.
Update: as reader psubrett pointed out, this is now available through Amazon for $12 shipped. Through 2/28, Shop4Tech.com has the Wii Twin Charger Stand with Rechargeable Batteries on sale for $17.95, before 17% off coupon code FT17 lowers it to just $14.89. These allow for up to 25 hours of game play per charge via USB. Shipping is free and there is no sales tax (except CA).