Recently, I installed Fedora 17 in my Desktop. Fedora 17 is cool but problem is that close button is on the Right side. But I am an Ubuntu user and used to everything on the left side. So, I do a little hacking in the Gnome-Shell and move the close button to left from right.
Open terminal and switch to root user
it will prompt for root password and then type following command..
gsettings set org.gnome.shell.overrides button-layout "close"
Done. Enjoy the Ubuntu style.