Jesus, Do you not want the user to see the info for security reasons or for displaying nicer URLs? If it is the later, you could use a form POST instead.
Is this user specific information or application level information? If it is the later, you could user property files or the like.
If it is security related info specific to one user, you need to store it in an external source (like a database) and have the second web app look it up by a key. This key could be user id if the user logs in or some value that you pass between the two apps.