dust bunnies, Wikipedia agrees with us.
Dust bunnies (or dustbunnies) are small clumps of dust that form under furniture and in corners that are not cleaned regularly. They are made of hair, lint, dead skin, spider web, dust, and sometimes light rubbish and debris, and are held together by static electricity and felt-like entanglement. They can house dust mites or other parasites, and can lower the efficiency of dust filters by clogging. The movement of a single large particle can start the formation of a dust bunny. and slut's wool.[