Linux only: If you're a recent convert from Windows to Linux, you might wonder how to easily launch the Task Manager equivalent with a shortcut key like you can on Windows. Here's the quick and easy way to do it.
Over at the How-To Geek site (my home away from Lifehacker), writer Justin points out that you can easily assign a shortcut key to Gnome System Monitor by heading into System -> Preferences -> Keyboard Shortcuts and adding a new shortcut key with the command set to gnome-system-monitor. Once you've done so, you can assign any shortcut key you like to pull up the task manager. It's a simple tip, but very useful for anybody just making the switch away from Windows.