The sniffy project can trace/log the data of any pseudo terminal in the system. Due to the way the terminal works, such a terminal trace provides complete information of what happened on the terminal screen, and sniffy is able to display/replay this information. It consists of a kernel module able to connect/hook on the pseudo terminal, a program to display the contents of any pseudo terminal on the fly, a daemon process tracing the pseudo terminal content into the file, and a replay program to replay any stored pseudo terminal session.
ansistego provides terminal-level steganography for scripts and other ASCII files (ie, protection against 'cat'). It intersperses a text/script with commented ANSI codes that cause most terminals to clear sensitive lines as soon as they are written. Only a specified front text appears. The front text is embedded in the script using ANSI-cloaked comments, so that the text appears unaltered when the script is viewed with cat, but the script can be run without any decoding stage.
Libptytty is a small library that offers pseudo-TTY management in an OS-independent way. It was created out of frustration over the many differences of PTY/TTY handling in different operating systems for use inside "rxvt-unicode". It also offers session database support (utmp and optional wtmp/lastlog updates for login shells) and supports forking a proxy process after startup and dropping privileges in the calling process. It offers C++ and C-only APIs.
S-terminal lets you create a secure X terminal. Regular X terminals pass unencrypted data between you the remote machine. S-terminal creates an encrypted tunnel through which all X traffic passes. It replaces the remote xdm login screen with a local application that collects username and password, then sets up an ssh tunnel to the remote host and starts a session. It is highly configurable both in appearance and behavior, and deployed S-terminals can be remotely administered. Best of all, it can be added to a KNOPPIX CD to create an instant, bootable, secure X terminal CD.
Multixterm creates multiple xterms that can be driven together or separately. It can be used to login via SSH to multiple hosts and control them simultaneously, or for ad hoc things where you want to see the results as you type. Each xterm may also be driven separately. Multixterm is scriptable so that you can easily fire up, for example, a dozen xterms with a single command, tiled nicely on your screen. In addition to SSH, multixterm can drive rlogin, telnet, passwd, or any program that runs in an xterm.