step 1 :: position an RFID reader between the elevators/stairway.
step 2 :: as ITP'ers enter the floor, the reader identifies users and sends request to database and looks up messages left for users.
step 3 :: messages are display on LCD (or projected on wall) as the user passes by.
step 4 :: as user passes screen the message fades away. if multiple ITP'ers pass by at the same time, multiple messages are displayed.