A new Feature of the Day for GP 2013 that is sure to be a hit is the new Reconcile IV to GL
Feature of the Day: Reconcile IV to GL – Inside Microsoft Dynamics GP – Site Home – MSDN Blogs
General Ledger & FinancialsTips & Hidden FeaturesGP 2013
Archived post from 2012. Dynamics GP and the links it points to have changed since; check current documentation before relying on version-specific steps.