Automatic Redirect

[Ethan]

I was wondering if a JavaScript exists that would automatically forward a viewer to another website but only once per time limit(i'd like to be able to set it around 20mins)

For example, a person going to http://www.google.com/ would be redirected to http://www.yahoo.com/, but this only happens once each time they visit google and will not happen again until they close and revisit google.

I hope that makes some sense.

[RowdyRed94]

You'd probably have to track it in a cookie. Does the script have to already exist?