ISO: Motion Detector Gadget

I'm looking for a device that will respond when my cat walks by. I know we can find a motion detector at our local home improvement, but I'm looking for the electronic device to which we can attach a feather and it shakes, inticing kitty to lunge.

We've got the Panic Mouse but it's eating thru batteries like milk shakes, causing Pip lose interest.

Any ideas?

Update

Andrew and I were at PetSmart and found PanicMouse 360 -it rocks. Unwittingly, we bought it because 'NayNay was jonesing for Pip's PanicMouse each time I turned it on inside the studio. Pulling the PanicMouse 360 out of the box, we discovered that the designers must have had a focus group: the on/off button was separated from the speed button and now include a timer -so kitty can increase him time in 15 minute increments.

I'm training 'NayNay like Pavlov's dog, hoping he'll learn each time he presses the timer, the PM360 will activate. At least this way, it doesn't eat the batteries like candy.