In its simplest form, bartering involves exchanging goods and services without money. These days, barter business exchanges have gotten so sophisticated that a meeting planner could "buy" a room rental from a hotel and "sell" planning services to another company in a different state. International Monetary Systems (imsbarter.com), one such exchange, did $106 million in trades last year through 23,000 people and businesses. Before signing on to one of these sites, make sure they list traders and services in the destinations where you do business. Also, the sites do charge fees (IMS, for example, gets a 7.5 percent transaction fee per barter). Before signing on, consider reaching out through your social networks for free opportunities to barter.