Not sure if anyone's mentioned this already, but last night I ordered a coat to be delivered to my local store (so no delivery charge).
After payment, it displayed the message "order in the next 30 minutes to get free delivery".
So ... I ordered the same coat, to be delivered to my home address for free. When I collect the in-store one, I'll just return it straight away. So next-day home delivery for free!
Not sure if it will work for everyone, or for how long, but thought it was worth a mention.