One of the controversial decisions made by the Gnome 3 developers was to do away with applets. For the most part I agree that applets were not very useful, but one applet I did use was the system monitor. To be able to see at a glance if the cpu or memory was being overloaded was a great convenience, and one that is sorely missed in Gnome 3. The good news is that this new system monitor extension from paradoxxxzero brings back most of the functionality of the old Gnome 2 system monitor applet.