I think its better for her to be in safe hands, so to speak, then go it
alone, when she may get into a predicament.
I know what you mean about travelling. Ours hate it. Even our Aunt's cat got
out of the car, never to be seen again when they stopped enroute. They left
a window down just a bit too far.

Jason

I have left mine for 4 nights already when I had to be in hospital but
I make sure they have plenty dry food, water, toys and I leave television
on for them [On Animal Planet :-) ]  plus someone stops in evening and
cleans litter box and gives them their canned food.

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Per Qwerty:

I'd also consider what an upset cat could do to the inside of my house over the
course of 3 days.

We haven't left ours yet, but the current plan is to leave it in the garage with
access to the outside via a partially-open garage door (which is how it lives
during the day anyhow - it only comes in at night...) and have somebody come by
to check up on it every day.

OTOH, my daughter and her husband went to some kind of craft/folk festival this
year and left their four cats basically on their own for a week.   They had a
feeder sort of like a bird feeder that held a few pounds of cat food.  

OTOOH, that was a rural environment, three of the four cats were barn cats, and
the same person that came by daily to take care of the horses and dogs probably
checked up on the cats....

I have done both over the years, but I much prefer leaving our cats at home.  
and I think they much prefer to be there, even in the absence of their owner.  
We have food and water containers that automatically keep the bottom dish
full.  Although they also eat canned food when we're home, they do just fine
on the dry food for short (less than a week) absenses.  I always leave a
radio turned on in one room, and a television turned on in another room.

Your 3-day absence should not be a problem.  

I'd definitely say leave her at home if it's just three days.  Especially,
if it may not even be three full days.  For example, if you're counting say
a Tuesday as day one but you're not leaving until Tuesday  morning, she's
still seen you on Tuesday.  And if you're counting the day you come back as
a day, she will still technically see you that day.  I visit out of state
family for a long weekend every so often and it's not really three full
days. My cat has always acted much more needy and clingy after I board her.
The last time she literally clawed at her carrier and cried (she's never
done that the other two times I boarded her).  She usually just sits in the
carrier and looks around. Then she clung to me for the next week.  She's
usually independent unless it's time for bed and then she wants to be on top
of me.  But when I leave her here for the same amount of time, she comes up
and purrs and I hold her for a few minutes and then she's off to the fridge
and begging for some of her canned tuna.  Then she leaves me alone until bed
time.  I think it scares them because they don't know what's going on.  At
least at home, they know you always come back there.  Also take into account
your cat.  Mine gets into things, like the cabinets when I'm gone, but she's
never knocked anything down to cause herself to maybe get cut later by
stepping on it.  And I have seen her maneuver around stuff almost seeming
careful to not knock things off.  Leave a tv on, leave her toys out, if she
sleeps in your bed then leave her access to it.  She'll be fine. It's the
long absences, like my 3 week Italy trip, that you need to worry about them
feeling abandoned, whether they are left at home with a cat sitter or
boarded at the vet.  After that, my cat wouldn't leave me for at least a
month and she was home with a friend of mine who's cat sat before who
actually "moved in" for three weeks.  But I digress.... :)

I have left my cat alone in my apartment for 4 days before.  Unlike some of
the other people here, there is no cat door, so she never goes outside.  I
filled 3 large litter boxes and put out plenty of dry food.  Longer than 4
days, boarding is better.

It's too bad you can't have someone come in once a day.  In this case, I
suggest you get water and feeding dishes at the pet store that supply
several days worth of food and water.  I think your cat will be happier.

MY experience:  have left a cat alone for 36 hours, with two boxes of
litter and plenty of food and two water bowls, in case he tipped one.
Clost off the bathroom so he can't go exploring under sink, look into
toilets etc.

For longer periods, I pay a cat sitter to come in once a day and do
food, water and boxes.

The only time I boarded him , he came home with upper resp. infection,
and had to take him to vet twice for treatment.  Surely, you can find a
neighbor or local teen who would love to help and earn a few bucks in
the process.  Ask your vet or at your local high school for some kid
who's reliable.
Or find ano. cat owner and work out a barter arrangement.  I know a
trio of cat owners who share the duties and no one keeps track, they
are just so happy to have someone come in.