CarbonKeys 1.3 - [info] [download]

Remote invisible key logger for Mac OS X written in RealBasic. Open source with extensive documentation.

Ncrypt 4.0 - [info] [download]

Encryption suite written in Java -- currently implements AES, RSA, and One-time pad ciphers. Open source.

Nlog 0.2 - [info] [Mac OS X] [Windows]

Network traffic logging -- implements regular expressions.

Spider Cipher - [info] [download]

Advanced 512bit symmetric key cipher written in Java and paired with relevant documentation.