Just because you don't have/want/like the iPad doesn't mean you can't have some fun with one anyway. Set any of these images as the background on a your friend's iPad, and watch the chaos ensue when they turn it on.
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Peruse a few childish iPad pranks in the gallery below. And to see them all on one screen, go here.
Happy pranking! (If you can do better, and we bet you can, share your best prank wallpapers in the comments. Just be sure to make them 768x1024...or 1024x1024 if you don't want them to pixelate when rotated to landscape.)