I usually use ccrypt to do simple file encryption from the command line in Linux but it has come to my attention that there is an easier way to do file encryption with openssl. From the command line on *nix machines that have openssl you can try the following.
To encrypt the file test1 and ouput to the file test1.aes.
openssl aes-256-cbc -a -e -salt -in test1 -out test1.aes
To decrypt the file test1.aes and ouput to the file test1.
openssl aes-256-cbc -a -d -salt -in test1.aes -out test1
This just makes file encryption easier because you can use any machine with openssl to encrypt or decrypt the same file. BSD, Linux, Solaris, Irix, etc. No more installing extra programs to do this if you really don't want to.