why is there no new tab extension like this

[cafevincent]

I am looking for a new tab extension that would allow me to set multiple sites that the extension would then rotate for every tab opened. One that displays second hand stuff around my neighborhood, one that shows videogames available for a toss-up, one that displays special discounts, you know, useful time critical things like that. currently I have to choose between all my time critical pages and use one at a time, and forget all others. I can't believe that every new tab extension only handles one single URL to drop to. Just a thought.