One of my cats is fascinated by anything mechanical and that includes my sewing machine. He's scared the stuffing out of me by batting at the needle as I sewed a few times. Thankfully he's never been hurt but I keep him off my sewing table now - it would be so horrible if he managed to get his little paw under the needle!
He sure does fear the vacuum cleaner though. If I so much as open the closet where it's kept he's off like a shot and hiding under the couch for at least a half-hour.