Millipede! Very cute and harmless. Fun for kids. They eat old vegetation mostly and might get into strawberries. But that doesn't mean you want them inside. Did you bring in a houseplant maybe? or do some yard work or have adjusted your sprinklers and made them seek higher ground? Just poke them and they'll roll up and you can pick 'em up and toss them out.

It's probably just a minor change in something like weather or lawn mowing schedule that is a big change to the millipedes that made them start coming in and it'll probably change back without you ever figuring out what it was.

Thank you, Fori! I don't have any plants inside (yet) but we've been doing quite a bit of yard work. Yoy mean we may have brought them in? Can't be. No garden boots allowed inside. No sprinklers, either. And I'm finding them in every room. Just one or two here and there.

Well, at least now I know what they are. :)