Blender Defender – Keeping cats off kitchen counters

Brian writes in about the Blender Defender. He writes –

Hi MAKE! I just finished the web page for my latest project: the Blender Defender. I have a problem with my cat jumping up on the counter and eating my plant up there, so I pointed a network camera at it and ran some motion detection software. As soon as my computer detects motion on the counter, it sends a signal to turn on an extremely loud blender and a strobe light, scaring the cat off the counter.