Help!

I finished my cemetery fence and am looking for something to add to my black light spider room. A particular air powered project bit the dust and a dark cloud has landed in my brain - I can't focus!

I have a 4 rpm rotisserie motor and want to make something moving, spider'ish, and somewhat large (large dog size). I have many 2' lengths of spare PVC pipe (left over from the fence), and a budget of about $50.

I was thinking of making a chicken-wire and great-stuff spider using the spare PVC pipe as leg segments, and use the motor to crank a few legs up and down from the hanging spider.

Any other ideas?

Any simple drawings for a crank-type thing? I'm still confused by that FCG.

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My other option was to take the motor and put it inside a torso making the head slowly spin.

...must...think...!