Architectural CAD: Archicad
by The EditorArchicad from Graphisoft is a cross platform architectural CAD application for Mac OS X and Windows.
From the Graphisoft website:
Archicad gives users the ability to create great architecture and increase productivity. From day one, Archicad has been designed by architects for architects, and over the years it has gradually become more and more refined to allow its users to better:
Focus on design,
Manage change,
Evaluate design alternatives,
Collaborate,
Coordinate.

