Multisite Widget Mimic
This widget replicates other widget areas from any site in a WordPress Multisite!
This plugin is meant ONLY for WordPress Multisite installations!
Simply place the widget in the area you want it to appear and specify the blog you want to pull from by its Multisite ID (1 is typically the main site) and the widget area by its internal name (i.e. page-sidebar).
This widget automagically pulls the content from the other site and displays it as desired.