I've been surprised by how useful this has been over the past few months. Just last week I busted my phone USB charger by accidentally knocking it off the table and bending the connector. This was around 10pm, so I ordered a new one and it arrived around 10am the next morning on my doorstep, well before my phone ran out of battery. Call it a first world problem, but same-day (or next morning) delivery is a minor but surprisingly convenient luxury.