Newegg offers the TP-Link Dual-Band 802.11n Wireless N900 PCI-Express Adapter, model no. TL-WDN4800, for $38.88. Coupon code "EMCWHPA45" cuts the price to $29.99. With free shipping, that's the lowest total price we could find by $9, although we saw it for $5 less last month. This adapter offers the use of 2.4GHz band or 5GHz band at speeds of up to 450Mbps and features WPA/WPA2 encryption. Deal ends December 15.