Like greased lightning . . .

. . . That's how fast a flying squirrel runs when chased through the living room by two cats.

And it's as hard to catch as a greased pig, as the kitties learned after romping through the house after it all night long -- and as we learned the next evening when the chase resumed during dinner.

It took a day to figure out what the thing was. Mice are common, especially in winter, but this guy was too big. We kept seeing it streak across the floor between furniture, too fast to identify. Finally my husband got a glimpse that told him it was bigger than a chipmunk with a similar tail, but not russety brown, no stripes down the back; gray or beige, smaller than a squirrel. Definitely not a rat.

Once hubby joined the fray, which moved into the basement workshop, he got close enough to look the critter in the face, up in the rafters -- big black button eyes looked back -- and to get a hand on its hindquarters before it squirted free and sailed past his head about ten feet to the floor, disappearing again under the machine tools and engine parts.

A flying rodent! That was the big clue. A year ago summer, we found a flying squirrel climbing up the basement wall in broad daylight. Until then, we'd been unaware that flying squirrels lived this far north. But we had been aware of critters living in the roof gambrels and the walls, scurrying around between floors now and then, and driving the cats nutty. We'd always thought the noisemakers were chipmunks or mice.

Neither critter is as bold (or tame? or tired?) as this one, which kept sticking its face out right in front of the cats, allowing us to get sooooo close before it shot away. I finally donned gloves and followed the cats around until they had the little guy cornered. Then I pounced! -- and caught him before the cats could and scuttled him outside. He fit with room to spare between my cupped-together hands.

End of excitement. We hope he found a warm place to crawl into, plus some food. Most likely, he's back in the gambrel through that hole we can't find, and the scurrying we next hear will be him running his usual route.

As long as he stays up there, we'll live and let live. And the cats will keep sitting on top of the refrigerator, staring at the ceiling.