At the moment, not a lot!
I think you can get a network (LAN) adaptor for it but other than that they are just there for future expansion.
Devices such as the controller chargers that you can get plug in to the USB ports but only draw off the requried power to charge your controllers and that is about it.
There are lots of hopes and ideas for uses of these USB ports and I for one would like to see a USB keyboard be devoloped so that when you send messages it doesnt take you 1/2 hour to enter a simple message!
