Here's an alternative to WiFi, which uses the electrical wiring of your house - turning a plug socket into a network socket.
It isn't really any cheaper than normal wireless, but I assume it would not have as much of a distance problem.
http://www.rivercomputing.com/shop/p...rtnr=DAB-1682U
I've not used it myself, or heard much about it, but here's the thread where I got the link:
"Powerline Network" thread at BXB