As a petty countermeasure to fight back against the marauding bands of skiddies that plague the internet, this server is running EndleSSH. EndleSSH is an SSH "tarpit" designed to lock up SSH clients for extended periods, and by extension locks up tools that attempt to brute force their way into many different servers. The purpose of this is to "trap" skids and prevent them from bothering other, potentially vulnerable servers. Also, it makes me feel better.
In addition to this, my server is also set up to record the IP addresses of everyone who gets stuck in this tarpit. With a hastily written Python script and some Bash kludging, the server maintains a list containing the IP address and locations of everyone who attempts to break in. That list, dubbed the Wall of Shame, can be viewed here.
The list is updated every 24 hours, assuming I set up the cronjob correctly.