BruteForceBlocker is a perl script, that works along with pf - OpenBSD's firewall (which is also available on FreeBSD and NetBSD) and its main purpose is to block SSH bruteforce attacks via firewall.
When this script is running, it checks sshd logs from syslog and looks for failed login attempts - mostly some annoying script attacks, and counts number of such attempts.
When given IP reaches configured limit of fails, script puts this IP to the pf's table and blocks any further traffic from the given IP.
Furthermore, the blocked IP is reported to the project site which enables users to share a list of abusive IPs. The list is publicly available at http://danger.rulez.sk/projects/bruteforceblocker/blist.php
If you are bored of those automated auth tries, you will be happy with this script. BruteForceBlocker is easy to use, simple, and effective.
For installation instructions see INSTALL file.