BruteNet is a system of the distributed brute force and distributed calculations built on user extensions capable to solve a great number of problems related to the partition on a lot of machines.With sample extention you can distribute brute md5-hash
Secwatch is an intrusion detection system using log analysis to detect service scan and other brute-force attempts on a server or other computer using system logs and will create temporary firewall rules to block offending IPs
brutesshd is an application written in c/php in order to prevent bruteforce attacks through ssh. Brutesshd uses iptables/pfctl tools to block this type of attacks