I've tried cardboard (cereal boxes, moving boxes, etc) and plastic sheets and aluminum foil (.foil did not turn out so well)What else, something less than $1?
Wrap tin foil around the usb wireless card not covering the metal chip, proved to increase range massively, saving lots of money.
You want to build what is called a cantennaCheck the link for a lot of good infoAlso there are DIYs on there to do it yourself.
Less than a dollar per what? Size? White PVC plastic sheet like is used for shower/tub replacement liners, but you probably have to buy several square feet Glass or mirror, especially if you keep an eye out and collect it from curb trash and learn to cut it yourself Thin metal called flashing sold at lumber and some hardware stores by the footAbout as thick as a piece of typing paper but stifferAluminum or galvanized steel.
