Seems there are all kinds of gadgets and widgets you can use if you'd like to add feed content to your blog or site. I haven't added any feed to my sidebar - yet; I'm trying to decide what type of content to highlight.
A few weeks ago I wrote about Feevy, which I have been using on my library's two teen blogs and our main blog. I think is a great tool for just this sort of set-up, and I thought that perhaps it would be nice if readers of the main (read: adult) blog could see at a glance what was going on in the teen blogs (without me having to constantly cross-post). Of course, no reads any of our blogs, but I do like to keep myself busy. Feevy's a good choice if you want something with a little (pre-determined) style in your sidebar.
If you are looking to place some news on your site, but don't feel like cobbling together the sources for yourself, then you might want to take a look at Moreover. I first saw Moreover at this site; it was also the first time I saw a live feed in action on a site. Moreover is a company that offers news solutions for websites, blogs, and publishers (like the NYT), but it also offers some free (ad supported) services for non-profit blogs. With Moreover you can choose the type of news content you want and generate a simple feed. Or, if you want to easily display it on your blog, Moreover works with FeedDirect's Webfeed Wizard. If you are a newsie, you might like this arrangement.
And, for the ADD among us, there's SplashCast. SplashCast positions itself as adding an "online TV channel" to your blog, and it focuses on "media" content (rather than just plain text, I guess). You can use rss feeds from places like Flickr and YouTube, you can create and add your own video/pics/audio - seems like there is plenty you can do with this. I think this service would be well-suited to teen library blogs, and regular library blogs that had lots of audio-visual content to broadcast. Right now, I'm finding the service slow (which could be because it's gaining in popularity), and the site a tad overwhelming; you might have to cruise around quite a bit before you really get a handle on what you can do, and how you can do it. But if you can figure it out, I'll bet you could do some very cool stuff with it.
And, naturally, there are the widgets that come with the major blogging platforms. If you are looking for seamless styling, using one of the widgets designed specifically for your blog tool may be the fastest and easiest way to go.