Alan Weiss, of whom I am a groupie, just published a quote that rocks my world. The full article is in the June 2012 issue of Balancing Act.
If someone pays you for your wisdom and advice, you’re a consultant—a “brain.” If someone pays you for your work and delivery, you’re a subcontractor—a pair of hands. Both constitute legitimate and respected work, but the former can charge based on value delivered and the latter can charge only on time spent on the job.