Mosquitoes have a knack of finding humans -- they can detect carbon dioxide and the alcohol octenol in our breath even from up to distance of 100 metres away. Now a US-based company, BioSensory, has developed a Dragonfly trap which releases just the right blend of those chemicals to lure mosquitoes. The trap has also the thermal lure that is just as warm as your skin. When the mosquitoes come near the trap thinking it to be humans, an electrostatic pulse kills them. Company officials claim that the trap does not attract beneficial insects. Up to 20,000 mosquitoes can be killed in just one night, they say (New Scientist, Vol 165, No 2228).