UPDATE: the commenters' verdict is unanimous: this is not a good idea, because it will damage the iron tip of the soldering iron. Thanks everyone!
These sort of sponges are sold for cleaning the tip of soldering irons:
Now, maybe it's an odd question -- but is there any reason not to use one of these kitchen scrubby things instead?
They are way easier to get, plus they are cheaper.
I'm wondering mainly:
- can you think of a reason why it could be dangerous to use the stainless steel one? (like, poisonous fumes or something)
- would it hurt the soldering iron tip?
It will destroy the soldering iron tip's plating. This will quickly result in it being unusable for soldering.
It's not dangerous. It won't emit any toxic fumes as long as it's just a stainless steel scrubber & not one pre-impregnated with soap like a brillo pad. But since it'll destroy the iron's tip it'll quickly be more expensive than brass wool.