ARD-Inspector is open source donationware which was made for OS X system administrators and consultants who need to recover a computer password from Apple Remote Desktop.
To make this tool, it required me to do some reverse engineering of Apple Remote Desktop. It uses the ARD Master Password to access to the AES encrypted database stored in the ARD users preferences. As you can see from looking directly at the source code, this tool does not make any modifications to the ARD file. Everything is read-only and no network connections are made. Your ARD secrets will stay safe, but now you can access it if you need to.
All documentation and download links can be found on the GitHub page for ARD Inspector.