Software
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.