There was a thread earlier this year about this problem, and no one had any solutions. I'm using FF 2.0, but I have the same problem regardless of what browser I use. I've tried both Camino and Safari. After a few hours of browsing, the browser suddenly stops loading new pages. At first only images stop loading, and then eventually pages won't load at all. Sometimes I have to Force Quit because menu items are also unresponsive. It won't even respond to keyboard commands. The browser is not frozen -- no beach ball -- it just stops working.