Until recently, practically everything "free" was really just the result of what economists would call a cross-subsidy: You'd get one thing free if you bought another, or you'd get a product free only if you paid for a service.

Over the past decade, however, a different sort of free has emerged. The new model is based not on cross-subsidies - the shifting of costs from one product to another - but on the fact that the cost of products themselves is falling fast.

Once a marketing gimmick, free has emerged as a full-fledged economy.

Forget squeezing millions from a few megahits at the top of the charts. The future of entertainment is in the millions of niche markets at the shallow end of the bitstream.

Scan the newspapers for the latest political or corporate crisis. All too often, you will find organizations and leaders incapable of delivering promises that, straightforward when articulated, became prohibitively complex in execution.

Promise management - the science of systematically connecting what we say with what we do -- is quickly becoming a differentiating factor in the decision making mindset of the twenty-first century. This has profound implications for corporations and leaders.