Here's how you can install Whisker Menu 1.4.0 in Debian 7 Wheezy. Whisker Menu replaces the default menu in XFCE.
1. Open a terminal window.
2. Type in the following commands then hit Enter after each:
sudo sh -c 'echo "deb http://download.opensuse.org/repositories/home:gottcode/Debian_7.0/ /" >> /etc/apt/sources.list.d/xfce4-whiskermenu-plugin.list'
sudo apt-key add - < Release.key
sudo apt-get update
sudo apt-get install xfce4-whiskermenu-plugin
According to Linux G:
Whisker Menu is an innovative alternative for the XFCE default menu, including a modern search bar and enabling users to easily access all the installed apps from the system, or access applications by categories. It also remembers the last 10 used applications.More at Linux G
Additional resources for Whisker Menu
Additional Debian Resources