In this case, the worm Caenorhabditis elegans (C. elegans) was found by scientists at Rutgers University in New Jersey, US, to losing its muscle mass and strength as it aged, without any accompanying loss in nervous system function.

BBC: Waistline secrets revealed by worms

Each player who joins a NiL server is represented by an Avatar, in this case a little blue worm.

CNN: Technology - Open-source, networkable shooter has Linux gamers buzzing

Like those viruses Bagle has an in-built timer that, in this case, will stop the worm spreading on 28 January.

BBC: The Bagle virus has tricked lots of people

If a truly malicious worm were to infect meters in a given area, there would be a best- and a worst-case scenario.

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