"Microoxen"

"Scientists in the US have managed to get single cells to ferry objects up and down tiny chambers. Harvard University experts say, in future, cells could be harnessed to perform micro-scale mechanical work. The researchers attached a cargo of polystyrene beads to the backs of green algae cells and used light to guide them up and down the chambers. Details of the work appear in the journal Proceedings of the National Academy of Sciences (PNAS)."