Cisco has the
refurbished Cisco-Linksys E4200-RM Maximum Performance Dual-Band Wireless-N Router for
$80 with free shipping. Features simultaneous 2.4 and 5 GHz bands, optimized for home theater streaming, parental controls, built-in UPnP A/V media server, can create separate networks for guests, and internal 3x3 MIMO antenna array.
eBay with Cisco also has it for the same price.
This is version 1. Refurbished version 2 costs more...
http://homestore.cisco.com/en-us/Routers/Linksys-Refurbished-E4200V2-MaximumPerformance-Wirelessn-router_stcVVproductId145289714VVviewprod.htm?icid=refurb_cat_spring_banner
I got the refurb version of this along with a Linksys AE2500-RM usb adapter, but the 5Ghz band didn't work (either with the adapter or an iPad 2). I just recently got around to updating the firmware and now 5Ghz works fine. It even feels a bit snappier than devices connected on the 2.4Ghz band.
Buy this one instead:
http://www.amazon.com/RT-N66U-Dual-Band-Wireless-N900-Gigabit-Router/dp/B006QB1RPY