I'm a little behind the curve on this one, but Nick put together a pretty sweet toolbar for Firefox and IE. It automatically discovers RSS feeds and subscribes to them in Newsgator.
It also has a nice feature that shows who is linking to whatever page you're currently on. It's an addictive little feature, particularly when you hit a rich vein of posts linking to posts linking to posts. Of course I'm not exactly impartial; there's a bit of my code behind the scenes powering that particular feature.
So go check it out!