For some reason, that attracts my cat to the door :-).  My mother usually
rings the doorbell when she comes home, so Kitty knows it's a sign that the
door will open.  I always thought she was afraid of cars because when
outside, car sounds make her hide behind me.  However, she seems to know our
car because when we get home, she's always waiting by the door.  I just open
it a crack and she sticks her nose out.  Sometimes I open the door a crack,
then shut it really quickly so it makes a loud thud.  That will sometimes
scare her away, but is beginning to work less often, and I can't do it when
she has already stuck her nose or paw in the crack.  The only sound I know
she is afraid of is that of a lawnmower, but that one isn't really
practical.  I'll try the can of pennies, as Lauren suggested (thanks
Lauren!).  Hopefully that will work for a few weeks (or at least until the
first snowfall, after which she won't want to go outside anymore!).

On the plus side of having a cat that loves to go outside, when I shake her
leash she runs to the door and sits so I can put it on her.  Then when she
comes inside, she'll sit just inside the door until I take her leash off.
Who says cats can't be trained :-)?

Thanks for the suggestion!  If I can't find anything else that works, maybe
we'll change our doorbell to a louder and scarier (to her) sound.  That
might finally work!

rona