Saw this pop up on my Facebook.
Amazon will be doing a daily riddle to solve to find an Amazon Locker. If you are the first person to use the code provided that day on the locker it will grant you a random prize (see site).
You can get the riddle via their twitter feed or on the linked website.
Enter the riddle answer into the name field in the search lockers at amazon and confirm it matches the location information given (https://www.amazon.co.uk/gp/css/account/address/view.html?ie=UTF8&ref_=mh_s9_acss_cg_x_5a1&viewID=searchStores&)
Runs 12th - 18th December.