Run the command "curl http://www.random.org/strings/?num=1\&len=8\&digits=on\&upperalpha=on\&loweralpha=on\&unique=on\&format=plain\&rnd=new" and pipe the output to the command "xargs -n1 echo $(date +%y%m%d%H%M%S)_" to generate a unique string with the current date and time.
curl http://www.random.org/strings/?num=1\&len=8\&digits=on\&upperalpha=on\&loweralpha=on\&unique=on\&format=plain\&rnd=new | xargs -n1 echo $(date +%y%m%d%H%M%S)_