The best part about iCloud, though, is in the features you can’t see. The service will sync your music and videos across all your Apple devices, and even match your other songs — for an additional fee. That means that if you download an app or take a picture with your iPhone, you’ll be able to access it on your iPad or Mac later. Apple offers users 5GB of online storage for free, with the option to upgrade to 10 GB for $20 per year, 20 GB for $40 per year or 50 GB for $100 per year.

Amazon Cloud Drive: Amazon’s cloud drive is another pure storage locker — no content creation or collaboration features are built into this service. But Amazon has the unique advantage of letting users store whatever music they purchased through the Web site right on their cloud drive.

If you’re an Amazon user and just want to access your files from any browser, the cloud drive is the simplest option. But if you want any other bells or whistles, such as the ability to share or edit, you’re better off with another service.

Amazon offers users 5GB for free or a variety of other storage options for an annual fee of $1/GB.

SkyDrive: Microsoft’s SkyDrive grants users access to Web versions of Microsoft Word, Excel, PowerPoint and OneNote, setting it apart from other services. While you can make documents, presentations and spreadsheets in Google Drive, those who are a bit set in their ways could feel a little more comfortable using the familiar menus.

Sharing is easy on SkyDrive — users can e-mail documents from the service or share them on Facebook or Twitter through a single menu. The service also offers collaborative editing, though without a slick commenting system.

The desktop folder for SkyDrive works with PC or Mac, as well as for iPhone and iPad. New users can get 7 GB for free, 20GB for $10 per year, 50 GB for $25 per year or 100 GB for $50 per year.

SugarSync: SugarSync is often overlooked as a service in the shadow of Dropbox, but this cloud locker is a user-friendly, simple service in its own right. It also comes with the added bonus of offering 5GB for free with several other storage options starting at 30 GB for $4.99 per month.

SugarSync is also a little more versatile in that it lets users sync specific folders to specific devices — good if you’re trying to keep some semblance of a work-life separation. It’s easy to start or stop syncing, as well, meaning you won’t have to drag things in and out of a desktop folder to manage what syncs when.

Sadly, you can’t create documents from within SugarSync, so this is yet another service that’s best for readers, not writers.

Users can get up to 500 GB for $39.99 per month — a good option until Google stepped up with its 1TB for $49.99 month offer.

Box: Box is another cloud service that gets a little less play than its competitors, but is a worthy option for anyone looking to move files up to 2GB to the cloud, particularly if you’re working remotely with other people. Users can invite collaborators to work on Web or Google Docs, or even Google Spreadsheets. They can also share files publicly or with other Box users. The service also stands out from the crowd because it allows users to add comments, assign tasks or start discussions on a given document.

Box offers users 2GB of storage for free, 25 GB for $9.99 or 50 GB for $19.99.

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Google Drive offers 5GB free, paid upgrades