What do I do with all the extra fat that dripped off my prime rib?

Thanks, everyone. I have made Yorkshire pudding and used it for roux. I think I am going to try using it to fry potato pancakes next. A friend suggested I mix birdseed with it and make a feeder for my bird friends.

Popovers as well.

I second Yorkshire pudding. Love Yorkshire pudding.

Use it to make the roux you'll need to make a gravy

You can make Yorkshire pudding. There's a great recipe for it in Silver Palate cookbooks. Save it and use it to cook with. You probably want to strain it before you cook with it, otherwise the brown bits may burn.