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A uP3 render pipeline plugin / hack to replace a particularly named or identified tab (folder) in the layout with a (configurably deep) fragment of layout containing Sakai IFrames.
Sakai tool portlets
First and simplest, just configured instances of the IFrame Portlet. More ambitious, JSR-168 that leverages Vishal's WSRP production work to grab tool content (not using WSRP, but similar approach).