A vibrating oxygen-hydrogen (O-H) bond on a water molecule can transfer energy to another molecule one hundred times more rapidly than physicists expected. Sander Woutersen and Huib Bakker of the FOM-Institute for Atomic and Molecular Physics in Amsterdam, the Netherlands, have used ultrafast laser pulses to excite the vibrational modes of water molecules and then probe how the vibrational energy gets redistributed throughout the liquid. Their results could explain why water is used to transfer energy between proteins and other biomolecules (Nature 402 507).