The Secret Shoe is a bespoke shoe with a hidden compartment in the sole to hold the likes of "the world’s smallest phone, a tiny video camera, a mini Swiss army knife, a tracking device, a choice of currency capsule (£50; €50; or $50); and the world’s most advanced contactless payment ring. The shoes can also accommodate a spare house key." A pair will cost you £2000 and are unlikely to result in a smooth TSA experience.
From Oliver Sweeney:
In addition to the items hidden within the shoe, the laces themselves are made from Kevlar. They can act as a friction saw cutting through wood or plastic, so should you ever find yourself zip-tied, you have a fighting chance of escape.