Among the most vexing challenges for entrepreneurs is how to avail themselves of the necessary services--intellectual venture capital--without burning through their seed money at a rate that makes further borrowing prohibitively expensive. Traditionally, professional firms have charged entrepreneurs a fee for their services, based on billable hours and effort. Yet in the past decade, an alternative model has emerged that obviates the entrepreneurs' conundrum while still satisfying the needs of the service provider.

The alternative is an equity-for-services arrangement, whereby...