Amazon.com has the
Netgear MA111 802.11b Wireless USB Adapter for $37 -
$20 rebate = $17 shipped. If you have a wireless network or are thinking of getting one, these make it really easy to get any notebook or desktop connected. Just plug it in a USB port, load the drivers, and connect to your wireless network. Don't expect great range from a USB adapter, but should work fine for most applications.