Linux only: Open-source app Preload loads portions of your most commonly used applications into memory -- resulting in faster load times when you start these applications.
If you're constantly using common apps like Firefox or Gimp you'll notice some greatly improved load times. Preload is a daemon that runs discretely in the background and will not disrupt your desktop in anyway. Ubuntu users can install preload with:
sudo apt-get install Preload
Preload is widely available in most repositories and works with all distros.Preload [Sourceforge via sheehantu]

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