drive new users to the join page with ajaix

i want an ajaix script created that would have a drop down show up on the right side of the page when a none member views more then a set number of pages. this drop down would ask them to login or join and would have a place for addition text to be displayed in the drop down depending on the number of pages viewed. there would also be a timer in the drop down so it would wait for 15 seconds once the page was displayed before it came down. all needed configuration information would be in the admin.

admin fields

max guest views
delay
text for page 1
text for page 2
text for page 3
text for page 4
text for page 5
position of drop down from the right in px