Linksys Wireless Repeater
I got this great link from hackaday.
It shows you how to configure 2 wireless routers to act as repeaters so that the computers in one router can see the other computers in the other routers… and you know?… share stuff & internet connections 
I know that with the LinkSys models, you have to buy a separate repeater… which of course costs as much as the router… no fun in that…
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