How to install terminal application globally?
Create a new folder somewhere accessible by all users.
Symlink a number of executables into that folder so that only the executables that you want to be accessible in all user accounts are in that folder.

ln -s /opt/local/yourport /path/to/your/folder/yourport

Add the path to your new folder to the top of /etc/paths. Since this file is read by all user accounts, it is added to the path for all users. However, since you're adding the new folder, you're not adding all the ports to everyone's path.