After using the Gnome Shell for a while, I kind of missed the Messaging Menu from Ubuntu. I saw an Applet for Cinnamon (a Gnome Shell Fork), which covered the Basics of it: easy access to the Messaging Applications.
Using Ideas from that Applet and other Gnome Extensions, I made little Extension myself which is available on the Gnome Website. For now it just shows your Applications in a Menu, but other Features from the original are already planed.
The Source can be found on GitHub, it’s open-source so feel free to help the Project.