For the past ten years, John Stepney has spent his nights and holidays delivering blood, breast milk, vaccines, medical equipment, test results, and other vital materials to hospitals in England. But he doesn't drive an ambulance or a car … he makes his deliveries by motorcycle. Stepney does all this as a volunteer, through the Nationwide Association of Blood Bikes (NABB).

"If you're going to go for a ride anyway, then why not give something back to the community at the same time?" says Stepney, 57, an avid motorcyclist who is also the chairman of Buckinghamshire-based NABB.

Thanks to their rising public profile—spurred by a recent "Point of Light" Award from the prime minister—the NABB has won a series of legislative victories that allow them (with proper training) to use sirens and run red lights if they're delivering time-sensitive materials. Volunteers can also now get tax benefits on their cycles.

There are more than 1,500 blood bike volunteers across the U.K., organized into more than 30 local groups. The riders make about 40,000 trips a year total to hospitals. The effort has contributed the equivalent of millions of dollars to the country's public healthcare system, speeding up service delivery for patients and freeing ambulances and professional personnel to focus on the most important cases.

Stepney says he has recently been contacted by bikers in Canada and Australia who want to start a similar service. The model makes the most sense in these and other countries that have public health systems, Stepney says, since the volunteer work saves taxpayer money.

Blood biking began in the 1960s in the U.K., when bikers didn't have a good reputation with much of the public. The idea was to "do something for the community that would give [bikers] a more upbeat image," Stepney says. The movement really began to take off around 2008, when the number of riders swelled, thanks to increased publicity.

Over the past few years, the bikers have increased the amount of breast milk they carry, after calls went out to mothers to donate extra milk for premature babies in need. Stepney conducted a pilot study of picking up and delivering the milk in 2009, and he helped develop a training program that ensures safety through strict control of temperature and other variables.

A recent request from a hospital also had volunteers carrying a fecal sample for transplant into a patient who wasn't responding to traditional antibiotics. Other deliveries include spinal fluid, rabies vaccines, and test results. (Learn about failings of the "last antibiotic.")

"It's an idea that is catching on," Stepney says.