Nanotubes made of a honeycomb arrangement of carbon atoms are famed for their strength, but Tienchong Chang of Shanghai University in China has found a chink in their armour. His calculations show that pinching a single-walled carbon nanotube at its end will cause it to collapse along its entire length. The effect is rather like toppling dominos, but in this case the electric charge along the tube, rather than gravity, drives the self-propagating collapse.
This weakness may prove to be a strength. Chang proposes new applications for nanotubes that collapse in this way, including a 'nanogun' for injecting or expelling molecules from devices.