While I don't see this as often as I used to, every now and then somebody suggests "securing" some service like ssh by running it on a non-standard port. There may have been a time when that offered some protection from uninvited guests, but that time is long gone: nowadays the folks on the outside will routinely try every port. Only the most naive of interlopers will be fooled by your use of a different port.
However, you may still have accomplished something useful if you have done everything else appropriate. For one thing, you have slowed the attacker down. Rather than just knocking at port 22's door, they have to go hunting for ssh. You've also made them "noisier", and thus easier for intrusion detection software to notice.
You might even be able to confuse him by running a false ssh service at the standard port and your real ssh elsewhere. The "false" ssh might use a configuration file that actually can't let anyone in - possibly wasting more of the attacker's time. This is a partial honeypot. I'm not sure this really does much (other than waste more of your bandwidth and cpu), but it might provide perverse amusement. Do keep in mind that a flawed honeypot is a dangerous toy; if you try to get too clever it may backfire on you.
I ran across this interesting idea for wireless lans: https://www.blackalchemy.to/project/fakeap/ broadcasts fake wireless access points, the idea being that your real router is hiding among them.
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More Articles by Tony Lawrence © 2012-07-20 Tony Lawrence
What do such machines really do? They increase the number of things we can do without thinking. Things we do without thinking — there's the real danger. (Frank Herbert)