One of my least favorite parts of Facebook is combing through my News Feed for a post I skipped past earlier in the day, or worse, earlier in the week that I now want to share or read. If I can't remember who shared it or I didn't like or comment on it when I first encountered it, then my search efforts meet with little success.
Thankfully, I found a Chrome extension via AddictiveTips today that helps solve this problem of how to keep track of News Feed items I may want to return to later. It won't help you if you access Facebook via its mobile app, but for those on a computer and using Chrome, there is Facebook Favorite.

After installing the extension, a button gets added to the right of Chrome's URL bar. And when you head to Facebook, you'll notice a small Favorite link gets added to each post, next to the Like, Comment, and Share links. If you click the Favorite link, it grays out and says Saved.
Now, with Facebook opened on Chrome, click the button the extension installed in the upper-right corner of Chrome and your favorited posts will be listed, albeit not in the prettiest of layouts. Clicking an item in this favorites list will open the post in a new Chrome tab.
At the top of your favorites lists are three buttons. The List button opens a list of all of your saved posts in a new tab, while the Feeds button does the same but in a poorly designed feed. In my experience, the tab that opened with the feed of my saved Facebook posts was littered with blanks spaces that said the post was no longer available.
Also, the "Clear cache" button that is supposed to delete all of my saved posts didn't work, even after restarting Chrome. (I am running Chrome on a Mac and tried both Chrome 33 and Chrome 34 beta.) There is a "Clear cache" button, however, at the top of the List and Feeds pages, which does work. And the List page provides an X button next to each item listed that lets you delete a single item.
It's a little rough around the edges, but Facebook Favorite does its main job well, keeping a list of Facebook posts you may want to double back to.