newegg offers the TP-LINK N600 802.11n Wireless 4-Port Gigabit Ethernet Router, model no. TL-WDR3600, for $68.99. This $30 mail-in rebate drops it to $38.99. With free shipping, that's the lowest total price we could find by $30. It features five Gigabit ports, two USB ports, detachable dual band antennas, and WEP, WPA, WPA2, WPA-PSK, and WPA2-PSK encryption. Rebate expires December 1.

A close price: Buy.com offers it for pennies more via this mail-in rebate.