Is there a good low-fat recipe for potatoes gratin?

My family is doing a potluck for Canadian Thanksgiving next weekend and I got ambitious and volunteered to do scalloped potatoes instead of my usual spinach salad.  I've never cooked any sort of scalloped potato dish and the only recipe I have is from Julia Child which is heavy on the butter and cream.

I'm trying to lose weight, my parents are on a low-fat diet (they love their turkey!) so I need a "light" recipe that is easy to prepare. Any ideas?

EDIT: I looked through all my cookbooks and there were quite a few recipes, but everything was high-fat except Joy of Cooking. Theirs called for quite a lot of butter but no cheese and cream was optional. They had sauteed bacon bits as an optional addition: I think that would go very well and a small amount of well-drained crispy bacon wouldn't be *that* bad, would it?

Heh - I think it's always gonna be an indulgence dish, but the recipe you described sounds like it won't kill you (!), and as long as the portions are small, go for it. Here's another one that's not totally loaded down: http://smittenkitchen.com/2009/04/simple-pota to-gratin/

It uses a little butter and milk, or no butter and half&half or cream, and only calls for 2 oz of cheese.

Here's one that might be good:

http://www.post-gazette.com/food/19990805schr amm1e.asp

My husband and I are doing the turkey for Thanksgiving this weekend, Mom is doing the veggies and my Aunt is baking the pies. We don't do the scalloped potatoes however, but we do mashed. I don't think Mom adds much of anything to them so hoping dinner won't be too much of a obstacle to navigate :)

I love scalloped and au gratin potatoes.  Here's how I do it. 

Make a large batch of this

Low Fat Cheese Sauce note:  Wondra Flour is also called gravy flour and is used for thickening sauces.  You can also use ordinary white flour, but be sure to whisk into the milk so there are no lumps when you begin, and you will have to stir it more often.  When the sauce is finished, taste it and adjust the seasonings, keeping in mind that the potatoes will soak a lot of it up.

Boil the potatoes whole until they are nearly done.  The centers should be a little firm.  cool and slice them. 

Layer them in a baking dish alternating potatoes and sauce, finishing with sauce.  It's best if the dish is not too deep.  Top with a sprinkle of bread crumbs.  Bake at 350F for about 30 minutes.  At this point you can cool it.  Just before serving, put it into the oven until it's bubbling hot and the top is golden brown.  Let it sit for a few minutes to firm up before serving.

Thanks for your responses, but I've decided to go with the Joy of Cooking's recipe. One big selling point is it has no cheese - cheese is my mother's biggest "fear food": she used to enjoy it but gave it up to lose weight. Bacon is actually better, and the recipe calls for 3 slices, chopped and cooked till crispy. And well-drained of course!