Belly button lint comes from your underwear.
Here is a strange web site that sells diapers for chickens. Apparently, there are people who keep chickens in the house as pets, sometimes whole flocks of chickens. Lots of people, actually, or else too many webmasters have too much time on their hands. According to Google, about 1,480,000 web sites are trying to sell chicken diapers.
Raining animals is a relatively common meteorological phenomenon.