Those of you who have a tin cantenna using a 802.11b USB dongle may be interested in the Belkin G dongle listed at CompUSA for $20.00 That makes a pretty cheap directional antenna.
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And with active USB extension cables, you can position the cantenna up to 80 feet from the PC or laptop.D-link's DWL-122 802.11b dongle can occasionally be found for about $10