I see many videos with this device/tool that looks like a small drill. No idea what it's called but I want one. If you have a clue about what I'm referring to and know the name, please post in the thread!
I know what you mean. Not sure what it is either, but you can achieve a similar effect, if not better, with an Oral-B electric toothbrush by removing the brush's head. There's a little metal "axis" underneath, for lack of a better word, which vibrates fast and allows for very high precision tickling.
I have a couple of these and I got them for like 5 or 6 bucks a piece. VERY effective tool which takes a delicate touch unlike that of an electric toothbrush where you can be more reckless. It takes one AA battery and comes with some of those disposable tips which are brutal between the toes and just along any body cleavage you may want w to explore. Only thing is you gotta constantly hold the button. Hope that was helpful and not too wordy lol.