newegg offers the refurbished D-Link Xtreme 802.11n Wireless Dual-Band USB 2.0 Adapter, model no. DWA-160/RE, for $12.99 with free shipping. That's $38 under the lowest total price we could find for a new unit elsewhere. (We did see a new one for just $3 more back in October, however.) It features wireless speeds of up to 300Mbps and comes with a USB extension cradle.

A 5-year warranty applies, although it's unclear who backs it.