Hi

use the commercial power line equipment which is now 500 meters or a Product Name:AMU-2405G-SMA
Product Class:Long Range Wireless LAN system
Features: AMU-2405G-SMA 802.11g/b 500mW , AP/Client/Repeater/Bridge; LED Wan/Lan/Power; Lighting arrestors protection; Stainless Steel adjustable mounting bracket;No internal antenna panel; Plastic outdoor weatherproof case; -30c~65c ,120/240~48vdc power ,up to 30km with Yagi, 16-dbi gain[not included .the unit will work non line of site for about 1 mile and connect laptop. as the 16 db yagie will pick up the weak signal from the laptop. and the power range will bounce from many locations.

www.zigwire.net