Last month, McDonald's said it would attempt to turn the golden arches green by feeding the city's leftover cheeseburgers and French fries to earthworms. The process, known as vermicomposting, will be launched in Yuen Long, in the New Territories, next month and is being hailed as one solution to the world's overflowing landfills. But if you're having trouble envisaging one little wriggler making light work of a Big Mac, rest assured there'll be plenty of the critters to get the job done - 80 million of them, in fact.
They may not be the most visually impressive creatures in the animal kingdom, but compost worms can eat their own body weight in food in just 24 hours - and they are not fussy. The worms at the Yuen Long site will process between 50 and 200 tonnes of organic waste every day.
The recycling process will see the earthworms munch their way through the leftover food, converting it into a waste product known as castings. Filled with nutrients, the worm waste will be used as a fertiliser for the booming organic-farming industry, providing a natural alternative to chemical fertilisers. The process produces less greenhouse gas than the traditional waste cycle.
There are more than 5,000 species of earthworm and the ones earmarked for this project are not the average garden variety. The worms most commonly used in vermicomposting are known as 'red wigglers', or red earthworms.
But if you want to do your bit for the environment, there's no need to wait for your leftovers to be sent to Yuen Long. An industry has sprung up based around 'worm power' and various companies sell small bins filled with the creatures that will do the same job.
Variations of vermicomposting have taken advantage of the worms' unfussy diet, which extends to animal, and even human, waste. Some ingenious souls in Australia and New Zealand have used the worms to dispose of faeces in composting toilets. This is especially useful in remote areas of national parks, where the lack of running water means flushing toilets are not an option.