Last weekend I ordered some stuff from Amazon - a USB memory thingy, and some DVDs. I told them to "group my items into as few deliveries as possible", to save money and also out of an embarrassing slightly hippy tendency to grumble about the waste of excessive packing materials. They do say that occasionally they'll split an order anyway, if part of it is excessively delayed, but ...
They sent five packages, all on 29/11/2008, at 06:10, 11:52, 16:16, 16:41 and 17:02.
It is obviously through efficiencies like this that they have attained their current dominance of the book/CD/DVD market!