You can go around your neighborhood on trash day (or swapmeet, craigslist, etc) and snag an old stereo receiver. Then connect the LFE out of your receiver to the input of your "throw-away" receiver. Assuming you get something with about 60 watts per channel, it'll sound ok, and it'll be better than nothing. It'll be a plus if you could even bridge the 2 stereo channels.
I had an Radio Shack Optimus 12" sub in the bedroom with an old dolby digital receiver for about a year and it sounded good enough to rumble.