How can I check if a visitor to my site has been there within the last 10 minutes. I'm explicitly talking about visitors and not users.
Reason: I have the small banner from http://www.explorerdestroyer.com which I use in my blank-master. Sadly this will display it continously on every single page, but I only want to make a reminder to the user every time he visits the site on the first page, but not on any others. That's why I asked for the 10 minutes. If he has been to the site in the last 10 minutes, don't bother, otherwise display it.