/raises hand
Some knuckles, back, neck, right knee, and (especially!) toes.
Anatomically, the toes and fingers are very similar, so we can’t say if it does any harm. You may want to curb talking about something that would seem to be a sure way to seduce you, though. It’s your call. For all I know, you might want everybody to know the best way to seduce you. 
I concur that cracking your knuckles or any other joints can be immensely satisfying. I, myself, have the absolute NEED to crack my sternum from time to time. It feels soooooooo good! However, I want to echo what The Master said in his tome: “…And it certainly doesn’t do much for your standing in civilized society.”
Please, please, please - do not do this in public. It’s pretty much the same thing as grooming yourself - flossing, cleaning your earwax, trimming nose hairs, etc. This is mainly because to some, the sound can be terribly grating - not unlike nails on the proverbial blackboard. It’s not to be done in public.
It’s one of those wonderful private pleasures, but please keep it to yourself.
Only if there’s a real controversy. If the controversy is fake, such as with vaccines, you can’t conclude that it’s not beneficial or harmful.
Don’t think I’ve ever seen any knobby toes.