Relatively cheap and worthwhile is this electrical parachute. Connects with 2 mm bananjacks, the standard jacks of most electroboxes (not included). It’s made from rubber and closes with two small buckles (it’s therefore adjustable).

The two conductive electrodes on the inside are made of soft material with a relatively high resistance, which makes this toy not a painful but a ticklish one. If you’re more masochistic, use the titclamps 6717!