Dog mess: to most of the population it is a bio-hazard about as welcome and useful as syphilis.
Even those required to collect it approach it with a plastic bag and a grimace. But for one former banker, it is the key to a tantalising civic and eco-energy revolution.
After three years of development work, Britain's first commercial-scale venture to convert the pungent scourge of pave-ments into a source of free heat and renewable electricity is set be unveiled.
An unnamed English local authority is involved in final negotiations to adopt the Streetkleen Bio system, a green energy project that will divert some of Britain's annual mountain of 700,000 tonnes of canine excrement into digesters capable of turning the waste into methane, CO2 and fertiliser.
The man behind the scheme is Gary Downie, a 42-year-old Scotsman living in Cheshire and former Manhattan banker who has designed the self-contained system capable of powering up to 60 homes at a time.