You came up in the list of Similar Threads when I recently posted a question with the tag terminal... I saw you have been 0 Reply since 2008, and so I was wondering if you had figured out what it was you were wanting help with? And even wondering if you are still working with Linux?
If not, I suggest the difficulty of the problem is the questions one is still left with after reading your description... in the years that have passed have you found your own solution you would like to share, or perhaps a new way to pose the question?
Were you looking for a screen saver? Or some kind of program to execute clear() after some time of idle inactivity? Something different? Something more?
# man clear
MANUAL PAGE FOR clear()