Mod Request: Bandwidth saver ?

[pagekeeper]

i thought there is some big boards out there i thought perhaps it would be a good idea to limit page views for guests perhaps some users can read all the posts and decide not to join up but if you have a barrier where by the user has already seen 5-10 topics or a certain amount of page impressions they get reffered to a page to signup " you've passed your daliy view allowance please signup to see any more threads or browse further "

just an idea .... if it already exists my oopsy can you perhaps tell me where it is otherwise, thought it would be a useful one or a complete crap one.