Buy.com has a Kensington WiFi Finder Plus for $20.99 after $10 rebate with Free Shipping.
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- The convenient, one-button WiFi Finder Plus quickly indicates signal strength for all 802.11b, 802.11b/g and active Bluetooth enabled networks within range. Compact device attaches easily to laptop carrying case or key chain. Silver case with 6 LEDs and built-in flashlight.