From the Wikipedia article at http://en.wikipedia.org/wiki/Barter
"Barter is a type of trade that doesn't use any medium of exchange, in which goods or services are exchanged for other goods and/or services. It can be bilateral or multilateral as trade.
Barter and money have different means of balancing an economic exchange. Barter is used in societies where no monetary system exists. When there is one, it is also used, especially in economies suffering from a very unstable currency." (http://en.wikipedia.org/wiki/Barter)
Ivan Tsikota on Barter Networks:
"The contemporary barter networks movement started with the establishment of the Swiss Wirtschaftsring, which was started in 1934. WIR still remains the largest organization of its kind. In 1993 it had approximately 17% of companies registered in Switzerland (i.e. around 77.000) and an annual turnover of €1.5 billion (Greco, 2001). By the end of 2000, its membership increased to 85.000, covering 20% of all Swiss companies (QOIN, 2011). It operates with the use of electronic money, which is formally pegged to Swiss Franc at 1:1 rate. However, it is not possible to exchange WIR-credit onto Swiss Francs, which assures that circulation is limited to cooperative members only. In this case it may be viewed as an advantage, since participating companies back WIR-‘currency’ by goods and services; and loans repayment is guaranteed by collateral.
In 2010, 400.000 companies were engaged in barter on the global arena with a volume of annual trade of approximately $10 billion (Stodder, 2009). QOIN (2011) reports that all 500 firms featuring in Fortune’s rating perform barter exchanges; approximately 750 firms are engaged in international barter trade. In 2008, the turnover of all barter contracts was estimated at $10 billion, and expected growth for 2009 was 15% (International Reciprocal Trade Association, 2011).
Commercial barter networks operate on a fee-based model. For instance, WIR implements three types of charges to cover costs: transaction fee, service charge, and interest on loans (Lietaer, 2001), and the charge depends on membership status." (thesis: Increasing Local Economic Sustainability)
- BarterQuest, http://www.u-exchange.com/
- Swap It Now, http://www.swap-it-now.com/
- SwapTreasures, http://www.swaptreasures.com/
- U-Exchange, http://www.u-exchange.com/
- Multiswap.net, http://www.multiswap.net/
There is a whole ecosystem of modules and software which support bartering mechanisms: