Top Greener Electric Supply via Amazon offers Prime members the Top Greener USB Combo Wall Outlet, model no. TU2154A, for $17.99 with free shipping. (Non-members can spend $49 or more to qualify for free shipping; otherwise, shipping costs $6.67.) That's $2 under the lowest total price we could find for a similar item, although we saw it for $2 less in December. It features two standard outlets and two USB ports.