My grandmother had several pieces that would make you laugh! This one will roll the fat off you, if you lean against it -- that's the claim, at least. (I assume this one plugs in, like my g-ma's did)
G-ma also had this thing with a belt -- you would lay the belt across your abdomen or behind, turn it on, and it would "shake" the fat off. She also had this gymnastic cot-like thing that would bent you in half, back and forth, with a little bit of abdominal effort.
As children, we thought all these machines were super fun! The bendy cot thingy was the best. We could make that thing fly!