The other day I ordered some new rechargeable batteries from Amazon. I chose a couple different items and put them in my cart. At some point during the checkout process I noticed the estimated ship date was a few days different between the products. Both items were more than $25 so I could order them separately and still get free shipping on both. I didn’t want one of the items to hold up the whole order, so I decided to place completely separate orders. The batteries arrived the other day, except Amazon had actually combined my orders into a single shipment.
While this probably isn’t that difficult from a technology standpoint, I thought it was a pretty cool optimization. Though I as the customer tried to outsmart Amazon and get the fastest possible shipping, they still crunched it down to one shipment.