This is a simple encryption tool to work with home-grown encryption algorithms. It can run as either a GUI, a command-line application, or a network proxy.

In command prompt you could use something like gcipher -C Gie test test2. Here the Gie is the cipher, test is the input file and test2 is the output file.

Or you could use the GUI:

[ http://gcipher.sourceforge.net/ ]