FreeOTFE4PDA is an "on-the-fly" (OTFE) transparent disk encryption program. Using this software, you can create one or more "virtual memory cards" on your PDA. Anything written to one of these cards will be automatically and securely encrypted before being stored. A PC version is also available, allowing data encrypted on your PC to be read/written on your PDA, and vice-versa.
The stunnel program is designed to work as an SSL encryption wrapper between remote client and local (inetd-startable) or remote server. It can be used to add SSL functionality to commonly used inetd daemons like POP2, POP3, and IMAP servers without any changes in the programs' code. It will negotiate an SSL connection using the OpenSSL or SSLeay libraries. It calls the underlying crypto libraries, so stunnel supports whatever cryptographic algorithms you compiled into your crypto package.