Today only. Newegg has the Rosewill RCP-E152C 150W Can Sized Silence Car Inverter for $40 - $26 off with coupon code EMCYTZT2511
[Exp 11/12] = $14
with free shipping. Sized to fit in a cup holder, aluminum casing helps dissipate heat, 5-Volt, 2.1 Amp USB port is suitable for charging smartphones and tablets.