These instruction will help you make a KDE desktop icon which starts the Sage notebook. Instructions for a Gnome desktop icon are probably similar.
notebook(open_viewer=True)
[Desktop Entry] Comment= Comment[de]= Encoding=UTF-8 Exec=/usr/local/bin/sage /home/martin/notebook.sage GenericName= GenericName[de]= Icon= MimeType= Name=SAGE Name[de]=SAGE Path=$HOME StartupNotify=true Terminal=false TerminalOptions= Type=Application X-DCOP-ServiceType= X-KDE-SubstituteUID=false X-KDE-Username=
To quit the Sage notebook: first enter ctl-c in the xwindow terminal running Sage, second enter ctl-d to quit Sage in the terminal, and finally close the browser (or browser tab) which was displaying the Sage notebook server.
For a picture for your icon, check out the Sage art at
http://www.sagemath.org/art/.
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