World's Smallest LED light?

This tiny LED light is called the NanoLite. It’s so small you actually stick it on the side of a key, pretty much, just about any key. Using it is a one handed operation. Just squeeze your thumb against the NanoLite button as you put the key into the lock and you'll be able to see the opening clearly. It can also provide a nice bit of light when opening car and home door locks. Actually it's good to open any lock that is normally in a darkened area. It uses a bright red LED to avoid night blindness that is often associated with a bright white light. There are other mini flashlights and key chain lights but with Nanolight you don't have to remember to carry them with you. NanoLite is smaller than a penny and a bit thicker. It easily attaches to a key with high-bond 3M adhesive. I’ve been using a NanoLite for about three years now and even though it hits up against other keys on the ring, it’s stayed perfectly in place all that time. The Lithium battery is not replaceable, but a spokesperson at the company said it should last for about 3 years. (Mine is still working at about 3 years.) Cost is $3.99, but a much better deal is to buy 4 NanoLites for $9.99 on Amazon. That knocks the cost down to $2.50. I just bought four more at Amazon at the link below:

NanoLite: Worlds Smallest Key Light (4 Pack)