One of my favorite Excel features, Pivot Tables, gets some love in the upcoming Dynamics GP 2010 release. The Excel Report Builder product will now be able to output Pivot Tables in addition to list style reports. Details at Inside Microsoft Dynamics GP.
Excel Pivot Table Builder in GP 2010
Excel & OfficeSQL & DataGP 2010
Archived post from 2010. Dynamics GP and the links it points to have changed since; check current documentation before relying on version-specific steps.