I was confused on what one of these were until I actually saw one. I was thinking these were those square, cardboard made chargers that are used in emergencies ususally (I saw one of those on QVC).
I went to Walmart yesterday and came up empty. For whatever reason, they didn't have them at my local one, but the mechanics had one. They carried thier name brand (whatever that was) for sale
I went to Sears today and saw their brand on sale through Sunday for $75. I believe theirs also did not have the AC outlet.
Finally, I got on Costco.com and found what I am buying. It does have an AC outlet and also a $20 rebate through Sunday (6/15). It is only available online (I tried calling my local Costco to see if they had it). With the rebate, it goes for $59.99 (plus S&H).