I guess it should be easily possible to open the ssh port with a fake ssh server and collect passes (I guess they aren't plain anymore and became hashes) and corresponding logins, e.g. a honey-pot. The idea behind that is to build a database and test my accounts on those. Has anyone done that already?
If you might wonder what benefit I would expect on testing my accounts with those passwords, I would argue that passwords might change during time and I could eventually anticipate a "successful" ssh-attack.