Dane-Elec's Media Streamer ($40) is an inexpensive accessory for sending media wirelessly to an iPad, iPhone, or iPod touch. The small, white plastic box has an SD cart slot as well as a USB port, plus a 2500mAh rechargeable battery inside that can be used to power your devices. By using a free app, or connecting over a browser, content can be shared on up to six devices at a time over its own Wi-Fi network, with no existing router needed. A micro-USB…