Newegg has the Linksys WUSB54GSC-4A IEEE 802.11b/g USB 2.0 Compact Wireless
Adapter with SpeedBooster Up to 54Mbps Wireless Data Rates Up to 128-bit WEP
, WPA, WPA2 for $18 - $10 off with coupon code EMCKJKF37 [Exp 1/10] = $8
with free shipping.
Link: http://www.newegg.com/Product/Product.aspx?Item=N82E16833124393