Cryptcat 1.2.1 for Mac could be downloaded from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The application lies within System Tools, more precisely Backup & Restore. This free Mac application was originally created by Cryptcat Team. We recommend checking the downloaded files with any free antivirus.
From the developer:
Cryptcat is a lightweight version of Netcat with integrated transport encryption capabilities. The application is a feature-rich network debugging and exploration tool that can create almost any kind of connection you might need. Netcat is an open source utility that can write and read data across network connections, using UDP and TCP protocol.
You may want to check out more Mac applications, such as CarbonErrors, Titan4 or iSauvegardes, which might be related to Cryptcat.