Adafruit USB 2.0 Powered Hub - 7 Ports with 5V 2A Power Supply
Add lots more USB capability to your Raspberry Pi or computer using this powered USB 2.0 hub. It adds a full seven powered ports, all at USB 2.0 speeds so you can use video cameras and other high speed devices (cheaper hubs are v1.1 and not as fast!)
The extra sauce with this hub is that you can power it with an external 5V adapter. There's a 2 Amp adapter included, which should be plenty to run even power-hungry cameras, WiFi adapters, and flash disks. The hub is fused for two amps using a resettable PTC fuse. Unlike cheaper hubs, this one has a single chip that provides all 7 ports instead of having two 4 port hubs chained inside. This is a great companion to your Pi, as they only have one or two USB ports and limited powering capability - we've tested it with great success on the Pi as well as our Mac and Windows desktop machines
Comes with a 7-port hub, a USB extender cable, 5V 2A UL listed power adapter that can be used with 100-240VAC wall power.