Vector metro (subway) map for calculating route and getting information about transport nodes.
Its GPL project for creating analog of pMetro (Muradov B.)
About 200 maps of subways are available:
http://translate.google.com/translate?sl=ru&tl=en&u=http://pmetro.su/Maps.html
(Maps have an open format and can easily be edited or created)
App available for many platforms:
http://qt-apps.org/content/show.php?content=146249
Also available for...
QGis Python Plugin to create named map themes to switch the visibility of all layers belonging to theme.
Experimental working prototype with functionality to include in future version of QGIS.