Maybe you use Freecycle, or are an avid product recycler all on your own. It could be you frequent eBay to scavenge, or visit the local dump for those occasional treasures. I use Craigslist personally, which goes to show the nature of some barter systems.
I am not especially well to do, but I have a good deal of... well... junk. I take apart my broken DVD players, alarm clocks, televisions, and anything else to get to those little bits and pieces. A few weeks ago I traded some of these items ( including transport ) for a nice 55" rear projection television.
Did you hear about these? There's this part inside of it called a "fresnel lens." I won't get into the nitty gritty details, but as a comparison fresnel lenses are to light as putting your thumb over a hose is to water. ( It focuses its energy. )
I've done similar things, within my household and amongst my friends we trade in parts and parcels often. It just makes sense, but big government has an easier time controlling and taxing money... so that makes sense for them.