> I'd like to shop for such a device, but I don't know what it's called.
I think it's called a "wireless bridge".
Any device with a wifi card and (at least) an ethernet port can do that.
So "any" wifi router will do the trick, as long as you can get it to run
a firmware that's not hopelessly restricted.
I'd recommend you look at the routers supported by OpenWRT.
Of course, if you can do it with cables (ethernet/powerline/younameit)
it's probably going to work better, but I guess you know that already.
Stefan
