Ubuntugeek posted a guide about installing gnome2-globalmenu from source for Ubuntu 10.10

This project introduces document-oriented concepts into GNOME, and improves GNOME’s respect for Fitts’s law. Most GTK applications work just fine with Global Menu.

There are several advantages by adopting a shared global menu bar in Gnome (thanks Matthew for organizing these):
* It works better with narrow windows, because the width of the menus isn’t limited to the width of the window. (This is a problem for Gimp and Inkscape especially.)
* It’s less confusing -- when two menu bars are visible on-screen at once, sometimes people choose the wrong one.
* Global Menu is the first step to move toward a Document Centric Desktop Environment ( ThoughtsOnADocumentCentricGnome ) which is, according to us, a long-term trend in DEs.

  How to install gnome2-globalmenu from source for Ubuntu 10.10 (Maverick)