Although some Mac Gems are full-featured applications, others are simple tools that do simple things—but things that some people need to be able to do. Take Stick Software’s free Jiggler 1.2 ( ), for example. Jiggler does just one thing: It jiggles your mouse cursor periodically to keep your Mac awake. Why would you want to do this? Perhaps you’re running SETI@home. Or maybe you’ve discovered the bug in Final Cut Pro 4 that can result in an application freeze during rendering if the mouse isn’t moved periodically. Or perhaps you’re engaging in the big no-no of installing an OS X software update on your PowerBook while running off battery. In each of these cases, Jiggler can keep your Mac from sleeping. (It can even be used to just prevent your screen from dimming if you’re enjoying a particularly cool screen saver.)
Now, granted, you could just set your Energy Saver preferences (in System Preferences) to “never sleep”; however, if you only need such functionality during certain activities, this would require you to change your settings, do your activity, and then change your settings back. (Leaving everything set to “never sleep” isn’t good for your Mac or energy conservation.)
And as simple as Jiggler is, it provides a few handly options: You can choose how frequently your mouse is jiggled, set Jiggler to only jiggle when you haven’t actually been using the mouse, and set particular conditions under which Jiggler should, well, jiggle (when the CPU is busy, when a writable disc—a CD or DVD—is mounted, or when a particular application is running).
Most users won’t have a need for Jiggler, but those who do will find it to be exceptionally useful.