Epson WorkForce DS-40 Portable Wireless Document Scanner
Most portable scanners are pretty lightweight and easy to take anywhere, but still require a physical connection. However this one from Epson can connect through a USB 2.0 port as well as with Wireless-N functionality so you can use it with a wide range of devices and wireless networks without a physical connection. It even supports iOS and Android, so you’re not limited to using this scanner with a narrow range of devices.
The scanners optical resolution goes up to 1200 dpi but only outputs at up to 600 dpi. It can scan a page at low resolution in about eight seconds up to about 30 seconds when scanning a page at higher resolutions. This model weighs just over one pound and is less than 12 inches in length, plus it runs on batteries so requires no physical wires at all when used with a wireless network.