One of the key advantages of Dropbox is that it's so easy to use—you simply set it up and then forget about it — but if you dig a bit deeper into the application you'll find that it has more strings to its bow than you might have realised.
Dropbox gives you 2GB of free space, but you get an extra 500MB for every friend you refer to the service. Dropbox also gives you 125MB extra just for tweeting about your love of the service.
Keep your eye on the official forums too; in the past many gigabytes' worth of bonus space has been given out for testing beta versions of mobile apps and entering Dropbox competitions.
You're probably going to need the extra storage of a Pro account for this one, but Dropbox can sync your iTunes library between several computers (at home and at work for example). This means your playlists, play counts and tunes are always available wherever you are. You'll need to move your library into the Dropbox folder, then point iTunes towards its new location — hold down the Shift key when launching it on Windows or the Alt/Option key on a Mac to do this. Once the library has uploaded (and this may take some time), you're ready to set it up on another computer. A word of warning though: only keep iTunes open in one location at any one time to avoid syncing conflicts.
Should you accidentally wipe the pictures of your son's 6th birthday party or an important company presentation, all is not lost — Dropbox keeps deleted files for 30 days after you've erased them. Head to the file browser on the Web and click the "Show deleted files" button to see them (they'll appear in a ghostly gray). Right-click and choose "Restore" to bring any file or folder back from the dead.
Both the iOS and Android Dropbox apps have a feature enabling you to upload your camera photos and video automatically, with no further steps required. Delve into the settings for your Dropbox mobile app to find the feature, which can be configured to work on Wi-Fi only if you're worried about data caps. You can then periodically delete the snaps and movie clips from your phone or tablet safe in the knowledge that they're safe and sound on Dropbox. A recent acquisition suggests this functionality will be fleshed out further in the future, as Dropbox looks to stay ahead of other auto-upload apps (Facebook and Google+, to name but two). This feature is also in the desktop client, by the way, and pops up whenever you connect a camera or external storage.
Two-step verification essentially means you need more than a password to set up Dropbox on a new computer or device, and it's something Gmail has offered for a while. Dropbox introduced the feature in August and while it makes the setup process slightly more inconvenient if you move to a new computer, it's well worth it for the extra account protection. Two-step verification can be activated from the Security tab of the Dropbox Settings page, and once it's up and running you'll need a code from your mobile as well as your password to configure Dropbox on a new machine. From the Security tab you can also review the computers and apps currently linked to your Dropbox account.
Sharing has been much simplified in Dropbox recently, especially if the person you're sharing with doesn't have Dropbox installed. You can share any file or folder by right-clicking it on the Web or your system and choosing "Share link". This link gives your contact full read-only access over the Internet, enabling them to download files as required. Some file types — PDFs, images and certain types of video, for example — are previewed in the browser, making life even easier. If you actually want to collaborate on files and folders with another Dropbox user (i.e. you both have full read and write access) then you'll need to use the Shared Folder feature (follow the "Sharing" link on the Dropbox homepage).
You'll need to add one of our favourite Web apps to the mix for this one, If This Then That. Sign up for the service and you can specify certain triggers—such as a new upload to Instagram or Flickr, or a picture you're tagged in on Facebook—which then cause the image in question to be sent to your Dropbox automatically. There are lots of possibilities once you've authorised IFTTT to get its hands on your various social media accounts—you can back up any of your Flickr photos with a particular tag, for example, or save your Instagram favourites as soon as you've hit the heart button.
With a little bit of work you can get your home computer to download torrents from anywhere in the world. You'll need to set up a Dropbox folder for torrent files, then get your client software at home to watch this folder for new files, downloading anything new automatically. If you're at work, or in a coffee shop, simply copy a torrent file to your designated Dropbox folder and it will be ready for you when you get back home.
If you've been around since the early days of Dropbox then you'll know that selective sync has been one of the most wished for features ever since the program was born. Well, it's now here in all its glory—right-click on the Dropbox icon, choose "Preferences..." and then switch to the Advanced tab to find the Selective Sync feature. This means you don't have to download your home movies to your work computer, or clutter up a laptop where there's limited storage space available, if you don't want to.
Favourite a file in the Dropbox mobile app on iOS or Android and it will be downloaded to the local storage system, meaning you can access it even without a Wi-Fi or data signal. Useful for reviewing that company report while your train goes through a tunnel, or listening to your most cherished album while trekking through the wilderness, perhaps.