Well, this isnt an ad bar but I am using it like one. CantBeatFree is a site that pays you to play games - complete offers and other things.
For the games - you let the timer tick up to full and refresh the page to earn a point. If you leave the page... the timer stops till you come back.
Now here is the trick: I open my browser and go to the site. I load the slots game. Then I open another browser and surf anywhere I like while my timer ticks away in the other browser. So while I am cutting coupons or searching or even typing up a blog post... I am earning money at CantBeatFree.