As a child I used to collect keyrings - yes, it was a bit of a rubbish hobby - but I enjoyed it, and had a fine (albeit tacky) collection consisting of all shapes and sizes. Nowadays, I don't get especially excited at the prospect of things to put on my keys - but I must admit to a slightly increased heartbeat when I saw the 'GlowRing', a small hexagonal plastic vessel (4.8 x 1cm) containing a minute amount of radioactive material. The radiation makes said GlowRing constantly emit light - no batteries or sunlight required. Now you're probably thinking that a radioactive keyring isn't safe, but the packaging states that it most certainly is - personally, I've been taught not to believe everything that I read, and I plan not to place the GlowRing anywhere near my intimate areas...

So how does it work? well, the keyring contains Tritium, a radioactive isotope of hydrogen which has a half-life of twelve years. As the Tritium degrades, it emits electrons which can be seen as light - hey presto - a glowing keyring! The Tritium is housed in a laser-sealed polycarbonate vial which has been designated 'unbreakable' (thank God!) - however, I'm not going to test it by hitting it with hammer, or running it over with the car... radiation poisoning isn't something I want in exchange for a thorough review.

The GlowRing's light should last for over ten years, which is especially impressive considering the fact that it needs no external power source to function. I should point out straightaway that the GlowRing's light is very dim, and in normal daylight you wouldn't even know it was glowing at all. However, in a pichblack room its radioactive light is plain for all to see, and is visible up to thirty feet away. The GlowRings are available in three different colours - blue, green, and pink, and they can all be picked up for the reasonable price of £9.00 from amazon.co.uk.

The GlowRing is especially good for putting on your keys, making them easy to find in the result of a power failure - similarly, i've heard stories of night fishermen tying them to the end of their lines, although personally, I'm not putting anything radioactive near my rod...

The metal loop for attaching your keys is nice and large, and the product is water resistant up to thirty metres. In terms of its weight, the GlowRing isn't at all heavy, and can easily be carried round without weighing down your pockets or bag. All in all then, if you fancy an extremely cool and maintenance free novelty keyring, then the GlowRing may be right up your street. It could be seen as a little pricey at just under £10, but it's actually a great piece of technology, and can be used as a useful marker for keys, bags, or what ever else you want to mark - highly recommended.