GIMP Plugin Registry

To be honest I'm not even entirely sure what these are as I'm new to gimp but basically I know it depends on what your doing with gimp as to which plug-ins are right for you so for me I'm making artwork for CD's i.e front/back covers so what plug-ins and scripts are essential/worth having? even if they don't relate too much to what I use gimp for I'm open to any other recommendations.