Downy or Hairy?

The downy and hairy woodpeckers look nearly identical, but as you can see here, one is much much larger. The first time one of the hairy woodpeckers joined the fray at the feeder, I thought some mutant downy had landed. But the mystery was quickly solved, and now we have three woodpecker species at our house so far. (We also have flickers) As long as they are not banging on the siding, this is a blessing.