If you haven't heard about Android 4.2 Jelly Bean's "Daydreams", well, they're a screensaver-like app that runs whenever your device is docked, or charging. There's a handful included with the stock Android 4.2, but there's a hidden one, too - it's unlockable if you access the Jelly Bean "Easter Egg" animation.
Tapping several times on the Android version number under Settings, then About Phone will display a large Jelly Bean smiley face. Press down on this for a few seconds and you'll be prompted with a screen filled with even more delicious-looking jelly beans.
Once you've done this, the "BeanFlinger" Daydream will be unlocked. You can find BeanFlinger under Settings, Display, Daydreams. This unlocking should work on any Android 4.2-based device that supports Daydreams.
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