It may look like a toy, but a centrifuge made out of paper could dramatically cut the cost of analyzing blood and diagnosing diseases like malaria in places where standard medical equipment is hard to come by.

The device, called the Paperfuge, is described today in the journal Nature Biomedical Engineering. Researchers at Stanford University led by Manu Prakash built it using essentially just paper discs, some string, and tiny straws to hold a blood sample (the team also 3-D printed a plastic version). By twisting up the string and tugging on the device, it spins at up to 125,000 revolutions per minute. A minute-and-a-half of spinning is enough to separate plasma from whole blood, and 15 minutes of work will isolate malaria parasites if they’re present.

Prakash, who in 2014 was named to our list of 35 Innovators Under 35, is a pioneer in frugal science, a field that aims to develop inexpensive tools that enable important and often lifesaving work—with a focus on some of the world’s largest public health challenges. Prakash has developed a microfluidic chemistry lab that costs less than $5 as well as a microscope made of just 55 cents worth of materials. Like centrifuges, microscopes are key tools for diagnosing malaria, which can improve treatment for people who get sick.

(Read more: “35 Innovators Under 35: Manu Prakash”)