KNoFault is a tool that protects your files with XOR encryption. It can use a username and a password to encrypt, or it can any file as a key. When given an incorrect decryption key, instead of showing an error it will encrypt the already encrypted file with the new info. This makes it possible to encrypt a file several times so that only two people together can use it, for example.
CLNoFault is a tool to protect your files or plain text. Using XOR encryption, it can quickly encrypt data using either a username and a password of your choice, or an external file that will serve as a key. Encrypted files can't be recovered in any way besides re-encrypting them with CLNoFault with the correct user/pass combination or keyfile. CLNoFault is the console-based interface for the NoFault library (like KNoFault for KDE), so it is useful in scripts.