Woot offers TESSAN Surge Protection Outlet Splitter (4 Outlets, 3 USB-A) for $9.99 (reg. $14.61) free shipping with Prime. 

Product Description:
USB Multi Plug Outlet Extender, TESSAN Electrical 4 Outlet Splitter with 3 USB Wall Charger, USB outlet adapter cruise Essentials, Home, Office. TESSAN Multi USB charging station accepts the standard N American 2 or 3 prong flat pin plug. AC outlets are separated without blocking each other. 3 USB Ports compatible for charging your cell phone, tablet and more devices at same time.