Vegetable spaghetti is a wonderful substitute for pasta if all you are really craving is the sauce. It has a very light flavor and it is a very good vehicle for that homemade alfredo or marinara, as long as you aren't expecting the same taste as wheat pasta.

Some of you are having trouble finding it...it is widely available here in so California at nearly any grocery store, year round. However if that's not the case where you live, consider growing your own. They are cucurbita pepo, same species as pumpkins, and you grow them exactly the same way. Seed catalogs all have vegetable spaghetti seeds, and a few have semi-bush forms (takes up less space than regular vines). They can store for months just like pumpkins.

http://www.territorialseed.com/product/1113/221