Less drafty cat door?

Has anyone figured out how to make pet doors less drafty?  Have one for my cat in a spare room and leave the door partially open. Any suggestions, ideas, thoughts?  

If you have a low mounted cat door to the outdoors, you could try making an insulated tunnel to the door. Since the cool air will stay low, shape your tunnel so that the indoor entrance to the tunnel is higher than the door’s exit. That way your heat will stay in the house and the cold will stay outside.

good idea!!  this one is in a window - I think I can make a tunnel to cut the wind which seems to come directly in. thanks!

I've seen cat doors with 2 doors, one on each side of the tunnel/wall.  I wonder if this would work?

EDIT:  Oops, didn't read all the posts, Laurel posted this a couple hours ago.  =-)

The tunnel is a great idea.  Maybe put a second cat door on the bottom end of the tunnel as well.  Only one flap will be open at a time and it will stop or reduce the wind coming in with the cat.

Do you have the tunnel attached to a door or a wall?