Mono: llXorBase64StringsCorrect() will not compile. llXorBase64Strings() does. default { state_entry() { string data = "I like bananas."; // the data we want to encrypt string pass = "monkey"; // the encryption key string crypt; // for storing the encrypted data // convert both data and key to base64 and encrypt the data with the key // then store the encrypted data in 'crypt' crypt = llXorBase64StringsCorrect(llStringToBase64(data), llStringToBase64(pass)); llSay(0, crypt); // this could now be used to email the data around // someone without the correct key wouldn't be able to (easily) get the plaintext // decrypt it again, using the same key, and convert back to plaintext llSay(0, llBase64ToString(llXorBase64StringsCorrect(crypt, llStringToBase64(pass)))); // as you can see, applying the same key to encrypted data again decrypts it } }