This Windows-only cracker bangs against network services of remote systems trying to guess passwords by using a dictionary and permutations thereof. It supports HTTP, POP3, FTP, SMB, TELNET, IMAP, NNTP, and more. No source code is available.
Wfuzz is a tool for bruteforcing Web Applications, it can be used for finding resources not linked (directories, servlets, scripts, etc), bruteforcing GET and POST parameters for different kinds of injections (SQL, XSS, LDAP, etc.), bruteforcing form parameters (user/password), fuzzing, and more.
The RainbowCrack tool is a hash cracker that makes use of a large-scale time-memory trade-off. A traditional brute force cracker tries all possible plaintexts one by one, which can be time consuming for complex passwords. RainbowCrack uses a time-memory trade-off to do all the cracking-time computation in advance and store the results in so-called "rainbow tables". It does take a long time to precompute the tables but RainbowCrack can be hundreds of times faster than a brute force cracker once the precomputation is finished.