audio-entropyd feeds the /dev/random device with entropy data read from an audio device. The audio data is not copied as is, but first 'de-biased' and analyzed to determine how many bits of entropy are in it. This program is useful for systems doing many cryptographic tasks like VPN endpoints or GPG clients; it helps prevent the /dev/random device from being depleted and blocking reads.
CIPE (Crypto IP Encapsulation) is an ongoing project to build encrypting IP routers. The protocol used is as lightweight as possible. It is designed for passing encrypted packets between prearranged routers in the form of UDP packets. This is not as flexible as IPSEC but it is enough for the original intended purpose: securely connecting subnets over an insecure transit network.
crypt++.el is a package of Lisp functions that recognize automatically encrypted and encoded (i.e., compressed) files when they are first visited or written. The BUFFER corresponding to the file is decoded and/or decrypted before it is presented to the user. The file itself is unchanged on the disk. When the buffer is subsequently saved to disk, a hook function re-encodes the buffer before the actual disk write takes place.
dirtypgp is a quick-and-dirty wish script to run in a X Window environment. It is a workslate upon which clear or cipher text may be cut and pasted. A series of button controls then are used to convert to and from ciphered and clear text, encoded with the PGP package. It was originally written by Carsten Meyer, who released it under the GPL.