XOR Encryption
Simple implementation of XOR Encryption/Decrypting in various languages, including:
This implementation goes beyond the basic single-key model to use multiple keys in a particular sequence, making it that much more difficult to brute-force.
In these examples, I'm encrypting the same string with the same keys in order to keep consistency with the output, and to demonstrate that an encrypted string from a C program can be decrypted in a Java application, or any combination, so long as the keys remain the same.
For an in-depth explanation of the code, check out KyleWBanks.com.