Over at High Dynamic Range, Aaron Berquist is (freakishly?) infatuated with FieldService, Or: Product 949, You Sure Are Fine. Checkout his post to find out why.
In Praise of FieldService, Or: Product 949, You Sure Are Fine
Archived post from 2011. Dynamics GP and the links it points to have changed since; check current documentation before relying on version-specific steps.