I wanted to be able to run a command in the background, go off and do something else, and have GNOME Terminal notify me when the command was done.
The patch below makes GNOME Terminal flash when a command finishes and you're not working in that window. It also highlights the title of the tab inside GNOME Terminal.
A new terminal

Running a long command (for example a long file transfer or a build)

Getting on with something else while you wait
The terminal flashes in the task bar to let you know the command has finished
GNOME 2.22
- Check out VTE revision 2048 from VTE trunk (mkdir vte; svn co -r 2048 http://svn.gnome.org/svn/vte/trunk vte)
- Apply this patch (cd vte/src; patch < vte-beep-urgencyhint.patch)
- Build and install (cd ..; ./autogen.sh; make; sudo make install)
- Check out GNOME Terminal revision 3194 from the GNOME 2.22 branch
- Apply this patch
- Build and install (./autogen.sh; make; sudo make install)
GNOME 2.24
- Check out VTE revision 2185 from VTE trunk
- (No VTE patch required)
- Build and install (./autogen.sh; make; sudo make install)
- Check out GNOME Terminal revision 3195 from the GNOME 2.24 branch
- Apply this patch
- Build and install (./autogen.sh; make; sudo make install)
Both
- Put PS1="\\007$PS1" in your .bashrc or .zshrc
- Log out and in