Third parties are always filling in gaps. It is what they do best. Nyko is no exception to this, and the Dual Charger AC does one thing, and does it well.
Unlike the Xbox 360, when you turn the power of the PS3 of (or put it into standby), your controllers will not charge over USB. It is a really nice feature of the 360 - the power brick will stay on until the controller is fully charged, and shut off automatically.
As much as I like helping the Folding@Home project, I am not going to leave my console on over night to charge my SIXAXIS controllers. The Nyko Dual Charger AC is the perfect solution for this.
Inside the wrist-slicing bubble wrap you will find a wall plug (with handy folding prong) that accepts two USB cords, plus two USB cords.
The obvious use for this is to charge the PS3 controllers, but it is compatible with other USB devices that use a mini-USB interface - all but one device, however. You cannot charge the PSP with the Dual Charger AC. The USB cord to charge the PSP is different, however, and this product is marketed for the PS3 audience.
Simple to use, just plug the Dual Charger AC into a standard wall outlet, plug in one or both included USB cords, and charge your SIXAXIS controllers. The indicator lights on the controllers will tell you once you have a full charge.
This is a smart purchase if you have two or more SIXAXIS controllers and only the one USB to mini-USB cord that came with the PS3.