Chewing gum could detect malaria.

From MSNBC:

Chomping on a stick of gum could cheaply diagnose malaria and other diseases in developing countries.

Using a recent grant from the Bill and Melinda Gates Foundation, Andrew Fung and his colleagues at the University of California, Los Angeles are developing Maliva, a malaria-detecting gum that could offer cheap, new way to diagnose or monitor diseases.

[...] When a person chews the gum, saliva, containing molecules produced by the malaria parasites, pour into the mouth. The magnetic nanoparticles are tipped with antibodies that latch onto these very molecules.

After a few minutes chewing, the gum would be removed and placed on a paper strip. The nanoparticles, bound to the malaria proteins, would show up as a thin line. No line, no malaria.