If you have a standard set of projects that you import into every workspace, you can install the project importer workspace mechanic plugin and automate that process. Just drop config files with a .proj extension into your ~/.eclipse/mechanic folder.
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http://webobjects.mdimension.com/mechanic/
The source is distributed as part of WOLips, though there aren't any dependencies on any other plugins in WOLips. https://svn.objectstyle.org/repos/woproject/trunk/woproject/wolips/core/plugins/org.objectstyle.wolips.mechanic/
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