A daemon that creates realtime dynamic, expirable iptables rules to block/drop IP addresses attempting brute-force breakin attacks on a linux host via ssh or other mechanism. Highly customizable and extensible.
Sherlock Roams is a Python-based password auditing tool for Un*x-based systems. It uses a bruteforce approach on the shadow file (or the regular password file if that fails) to determine which users on your system have obviously insecure passwords.