Sitecore CMS 5.3.1 has a cool feature that not too many people know about. At least, I couldn't find it described on anyone's blog, so I figured it would be a good choice for my first useful blog post.
If you like using keyboard shortcuts, you might want to know what shortcuts are available in the Sitecore Content Editor. You can find a list on SDN, but I never want to take the time to find the right article myself and I often forget which shortcuts are available.
If you press ALT+F1 while in the Content Editor, it displays the keyboard shortcuts associated with each of the commands in the ribbon.