Ok, this isn't exactly GEO, however, for those producing and sharing media, Geo data etc... there's loads to know about social media and how to leverage these tools. I recently found some handy cheat sheets that are available for download (PDF). A simple request form is required (painless) and these handy sheets are pretty useful!
Facebook Keyboard Shortcuts: Facebook provides users with about a dozen of handy shortcuts that users may use for faster navigation through Facebook. For instance, Alt+1 will take you to your home page. Alt+M will take you to a new message screen. There are many more and this cheat sheet list them all, including codes for Facebook chat emoticons.
Twitter Shortcuts: Many people don't know, but ever since Twitter redesigned its website they have added a bunch of handy features including support for keyboard shortcuts. This cheat sheet lists all shortcuts that you can use to navigate Twitter faster.
Gmail Shortcuts: When it comes to Gmail there are a bunch of very useful shortcuts that make it easy to navigate and perform certain actions in Gmail. Download the Gmail cheat sheet. It's free.