I wrote an RSA encryption program in Python. Ke and Kd (the public and private keys) are created from primes of at least 100 digits.
The encryption interface is pretty easy to use. There is a box to put in plaintext and a button to encrypt it, which is dependent on who you are sending the encryption to (theoretically, everyone has a unique public/private key set). The encrypted numerical string is output into another box. This is what you send the intended recipient.
The decryption interface works the same way, only inverse to the encryption interface.
If anyone is interested in having this program to use for yourself, email me at: hanieldardin@writing.com.