You probably know this: you power on your machine, and immediately after you've logged in you manually start your two or three favourite applications. Why not have the system start these applications for you automatically? This short guide shows how to accomplish this under GNOME.
I do not issue any guarantee that this will work for you!
For demonstration purposes I will show how to make Pidgin (instant messenger) and Skype start automatically after the login. You probably have other applications such as Evolution or Thunderbird that you'd like to start - it works exactly the same way as shown here.