SeChat Applet - AES encrypted chat written in Java
To encrypt an email, simply type a key (which is then SHA-256 hashed, so the key can be of any length). Then enter your plain text on the lower text box, and click Encrypt. The output is given as Hexadecimal text which can be copied and sent through email.
To decrypt, copy all the encrypted Hexademial text and paste it in the lower box. Then enter the same key used for encryption and click Decrypt. The plain text is then shown on the upper text box.
Unfortunately, the Java Applet needs to be signed in order to get permissions to perform socket connections. If you want to chat using SeChat, you can download and run the SeChat.jar file. To run in Windows, simply double click it.