OpenStudio is a free plugin for the Google SketchUp 3D drawing program. The plugin makes it easy to create and edit the building geometry for EnergyPlus input files.
Version 1.0.3 of OpenStudio was released on April 14, 2009. The installer can be downloaded from the EnergyPlus website here: http://www.energyplus.gov/openstudio.cfm
This version also marks the first public release of OpenStudio for Mac OS X!