List of USB WiFi adapters, what is acceptible from newegg.com, and probably can work with GPL drivers:
Keep in mind that with many manufacturers, different hardware versions of the same model will often use different chipsets; and that it may also happend sometimes between units displaying the same hardware version.
Model: D-LINK DWL-G122 H/W Ver: C1 Chipset: Ralink RT73 How-To: http://luxigo.tiddlyspot.com/#%5B%5BD-Link%20DWL-G122%20-%20Elphel%5D%5D
Name: ASUS WL-167G, Ralink RT73 based link: http://www.newegg.com/Product/Product.aspx?Item=N82E16833320107 ~$20 information about Linux: http://www.murrayc.com/blog/permalink/2007/02/17/linux-compatible-wireless-usb-adaptor-results/ - post in the comments, "Jon Smirl Says: ..." Note: work with Kubuntu 7.10
Name: Orient XG-701A+, Zydas(Atheros) ZD1211BV based link: http://www.orientrus.ru $18 Note: SMA antenna connector
devices from this list: http://linuxwireless.org/en/users/Devices/USB
TRENDnet TEW-429UB http://www.newegg.com/Product/Product.aspx?Item=N82E16833156161 $50
3com 3CRUSB10075 http://www.newegg.com/Product/Product.aspx?Item=N82E16833105022 $44
IOGEAR GWU523 http://www.newegg.com/Product/Product.aspx?Item=N82E16833139116 $27 Note: work with Kubuntu 7.10
level one WNC-0301USB http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=2052810031+50011109&name=LevelOne $25
Resume: on the camera is an old kernel, w/o needed modules. Make a port of the "zd1211rw", "rt2570" & "rt73" drivers.