I was looking for a little app to randomly pick a wallpaper image from my directory of images to use as my wallpaper.
I found an application called wallpaper-tray which is a little tray app that will do just that.
apt-get install wallpaper-tray
Once this was installed i wanted it to run automaticly so i went into
System –> Preferences –> Sessions
Click on “Startup Programs” tab
Click on “New”
Add a name & in the command box put “wallpaper-tray”
This means that the app will run on boot, it now appears in the top corner & its neat little interface makes it easy to add directories for it to grab images from.