Money exists to reduce the inefficiencies of barter. But barter makes a comeback where money is suspect (think Zimbabwe). It also makes a comeback when and where people experience liquidity shocks (think U.S. circa now) and where they have access to cheap information exchange opportunities (think Craig's List).
Look at "Let's Make a Deal ... The growing role of barter in the marketplace" in yesterday's WSJ.
Modern communications have changed our lives (mostly for the better) in uncountable ways. Now add people (and businesses, according to the article) finding ways to cope with the recession.