reBlog is a tool that can be useful to a blog like this one right here, which consists of entries that talk about entries on other blogs a lot of the time. It helps you check the feeds of several blogs and publish some of the entries you find interesting in your own blog. It uses the excellent Feed on Feeds, albeit adapted, to display the latest feeds from your favourite sites, and then you have the option of publishing some of those feeds on your blog.
Movable Type and Bloxsom are supported right now, so you cannot publish to a WordPress blog using reBlog just yet, but I imagine it should be a simple affair to publish to a WordPress blog. After all, reBlog uses PHP, and the content is in XML. Let’s see how long we have to wait before we have a reBlog plugin!