Rohit Gupta made a portable wood speaker that can play from USB, SD , Aux and has FM. Project details at Rohit’s blog. Via the contact form.
Here’s an application note from Maxim: Enable automotive USB power – Managing the increasing currents, longer cables, and tight portable-device specifications This application note discusses the challenges of rapid USB charging of today’s portable devices (PDs) in an automobile. The PDs may not charge quickly or charge at all, especially the more recent power-hungry devices. […]