Solidify-wireframe script for blender 2.5
The script is very simpe to use, once installed via the user preferences->addons page, when you are editing a mesh, press Mesh->Edges->Solidify Wireframe, and the selected edges of your mesh will become solidified with quadrangular sections. A dialog will pop up to allow you to choose the section width. Enjoy!
Edit: In latest version, this script doesn't open a popup anymore, instead it sits in the toolshelf (T key), more the new blender way.