Topic: Sandboxing Cookies
I am wondering if there is any way to sandbox the cookies and anything else placed on my computer to the top level domain that placed it there. For instance, if a google.com page puts a cookie on my computer, only webpages with google.com top level domain address can access that cookie. No other webpages can access that cookie, nor can a google.com page access cookies other top level domains placed on my computer. This would allow for the benefits of using cookies without the cross-page tracking that can happen, effectively neutering so-called super-cookies.
For a bonus, it would be even better if this could be done through encrypting all of the cookies and files with a hash specific to the top level domain.