Now wait just a sec...each Apple store is getting deliveries (albeit small ones as far as the lines here in my area have proven) most days. I tried going on a Saturday at 6:30 a.m. to wait in line, but by that time there were already about 40 people in line at my local location. I had waited twice before in line and have found that the first folks almost always buy 2, so they do not get very far down the line before they are sold out for the day.
Last weekend, at a different local Apple Store, the magic time was 5 a.m. My BIL went at 5 a.m., in the rain, and was 4th in line. He was nice enough to purchase one for me too!
There are surely no guarantees that the store you are waiting at will get a shipment each day, but I have not personally experienced many days at the three near me where they did not get a shipment at all. So, if you are desperate, 5 a.m. seems to be the magic hour in the South Bay Area (San Jose, CA).