LitDev, a very active Small Basic Forum participant has started a thread with a bunch of Small Basic programs that illustrate fascinating optical illusions.  Here are some below – click on the link below the images and you can actually view them on your browser.

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http://smallbasic.com/program/?PVC930

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http://smallbasic.com/program/?CDV606

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http://smallbasic.com/program/?FMW356

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http://smallbasic.com/program/?CNR593

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http://smallbasic.com/program/?TTR706

Go check out the forums for more updates.  You would need to download the latest version of Small Basic to be able to modify and create new illusions.