Be careful of depending upon this, though.

I was going to be out of town for a few days. But the item I wanted had a good sale price. I ordered it and selected the slowest shipping option; the page said it would ship the Friday before my return -- perfect.

The next day, it had already shipped. I had to scramble a bit to make sure it wouldn't be returned as abandoned, before I returned (shipped to a shipping address that only holds packages for so many days).