Sink your toes into this: Beach sand can be used to make lithium-ion batteries that last three times longer than current models, according to a study published in the journal Scientific Reports.

"This is the holy grail: a low-cost, non-toxic, environmentally friendly way to produce high performance lithium-ion battery anodes," said Zachary Favors, a graduate student at UC Riverside, in a statement.

The idea came to Favors when he was sitting on the beach after surfing, and realized the material was made up of a high percentage of quartz, or silicon dioxide. Typically the negative side, or anode, of lithium-ion batteries are made with graphite. Silicon has been eyed as a replacement material, since it can store about 10 times more energy--only it's difficult to produce in large quantities and degrades quickly. But perhaps the silicon in sand could provide a cheap, abundant source of silicon.