Backup to another host through NetCat command. It can be useful if there is no space for local backup or just for file transfer between hosts.
nc -l -p 8081 >/tmp/nc.dump #just listen on port 8081 and rewrite to stdout
then send something in raw to remote host:
tar c /opt/music | nc -w 2 HOST 8081
cat /tmp/mp3.file | nc -w 2 HOST 8081
-w 2 - wait silence for 2 seconds at stdin of NC and exit
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