When it comes to cloud storage, there are a whole bunch of fluffy options up there in the proverbial sky. Maybe you need unlimited storage, or maybe you need it for free. Here's a list of the ones that are the best at what they do.
Best Beefy Free Service: MediaFire
There are a couple of big boys out there that offer a whopping 50GB for the low, low cost of zero dollars, and among them, MediaFire gives you the most for your complete lack of money. Along with its free 50GB, MediaFire's got clients for PC, Mac, and Linux with apps for iOS and Android. The main downside is that your uploads will be limited to a mere 200MB. But if you can handle that, MediaFire is the biggest, best locker you can find for free.
Mega is another one with a free 50GB to get you hooked, but for now it's just a web-app. Desktop and mobile apps are coming, and when they do, your desktop upload size will be unlimited, but until then you're stuck at 300MB and under. Otherwise, you could pay $15/month for 500GB of storage. And while the encryption is a bonus, hosting media on a site that the U.S. government hates is kind of a downside; you remember what happened to MegaUpload. But once it gets its app/client situation together, Mega will be the king of this hill.
ADrive is another strong contender with it's "personal basic" option. You'll get your 50GB, and a juicy max upload size of 2GB, but there's a bit of a price to pay, even if it's not in money. The personal basic option means no access to the PC, Mac, or Linux clients, but you will have ad-supported iOS, and Android apps. But the real bummer is mandatory banner ads and marketing emails. Sure, you can get around most/all of those with a little skeevy ingenuity, but those downsides make it a little less appealing than your other options.
Best Unlimited Service: Carbonite
Sometimes you need a limitless black hole of storage, especially if you're backing all your devices. And Carbonite is your best bet for saving everything. Unlimited space will cost you $60 a year, but it comes with PC, Mac, iOS, and Android functionality. And, best of all, you can set up Carbonite to just back up all your stuff automatically, so all your crap will be stored in the unlimited cloud without a thought. The only real downside is a 4GB max for uploaded files, but that's pretty large so you should be able to make it work.
Backblaze is the cheapest option out there at $50 a year for unlimited storage, but it doesn't have any Android support. So if all your devices are iOS, Backblaze is definitely the way to go, but if you have an Android, or might get one, you'll want to steer clear.
BitCasa is a little bit pricier than its competitors at $70 a year, but supports PC, Mac, iOS, and Android. Your first 10GB are free, but if you're going unlimited that doesn't mean much. It's main selling point is that it's the only one to have no max size for uploaded files, so if you need unlimited space specifically to back up your 4GB+ files, BitCasa is your winner.
Best Platform Hopper: SugarSync
Pretty much everybody's got PC, Mac, iOS, and Android on lock, but Blackberry, Kindle, and Windows Phone 8 tend to get left out. If you've got one (or all) of those, SugarSync has the kind of coverage you want. With 5GB free and 30GB at $5 a month ($60 a year), SugarSyc will consolidate files across PC, Mac, iOS, Android, Windows Phone, Kindle Fire, and BlackBerry. There's no max file size for upload either. No other service we found was able to cover more bases than SugarSync.
Insync puts up a good fight too with PC, Mac, iOS, Android, Blackberry, and Windows Phone, but it's not quite as versitile as Sugar. You'll get a better bang for your buck though, 25GB will cost you $2.50 a month ($30 a year) and there's a (large but still existent) 10GB limit on uploaded files.
Box comes close with PC, Mac, iOS, Android, Blackberry, and WebOS, but you're probably more likely to need Kindle Fire or Windows Phone. But on the off chance you're using a WebOS device, Box has got a free 5GB, with an option for 20GB at $40 a year. The max file-size for free accounts is a scant 250MB though and only 1GB if you pay.
Best Windows-Specific: Skydrive
Skydrive is a good bet for the Windows 8 faithful. Given that it is from Microsoft, it's going to fit well with their products. With 7GB free out-of-the-box and options for an additional 20GB, 50GB and 100GB for $15, $25, and $50 a year respectively, Skydrive's not a bad deal. Uploads are limited to 2GB, but if you're deep into Windows 8, the integration should pay off.
Best Mac-Specific: iCloud
iCloud is no stand-out in the grand scheme of things. Its free 5GB is typical, its 25GB for $10 a month ($120 a year) is pretty expensive, and its upload limit of 250MB is a bummer. But, its deep integration with OS X can make up for that, depending on how heavy of a user you are. It can handle iOS backups and has integration with Contacts, Calendar, Notes, and Mail. And if you've got an iPhone, the lack of an Android client is no big deal. But if you want a little more from your service, there are other options.
Best Overall: Google Drive
If you've got no specific, weird criteria and you just want something cheap-ish with room for growth, Google Drive has a good mix of the features you want. It's got the main bases covered with clients for PC and Mac, apps for iOS and Android, and a web manager. Its free 5GB isn't mind-blowing, but it's a fair bit, and only a few outliers offer more for free. It's upload size is limited, but to a huge 10GB which should cover most of your stuff. And if you're shelling out some cash, Google Drive's 25GB for $2.50 a month ($30 a year) is about as low as dollar-per-GB prices go this side of several hundred. The 100GB for $5 a month ($60 a year) is pretty killer too.
SugarSync is a pretty good all around bet with its 5GB free and hard-to-come-by unlimited upload size. If you're shelling out some cash, SugarSync's 30GB for $5 a month ($60 a year) isn't the best deal out there, but it's fair, and more than worth it when you consider the plethora of platforms it supports and the unlimited upload sizes.
Mega isn't quite there yet, but once it's up to speed it'll be hard to beat. 50GB for free is a crazy deal, but the lack of apps and clients—which mean 300MB upload limits—make it a little bit of a tough pill to swallow as a primary service. Once those are fixed though, it'll be a great deal.
Best Battle-Proven Standby: Dropbox
It's not quite a stand-out on paper, but we'd be remiss if we didn't mention Dropbox. It won't win on initial free offering (2GB) or price (50GB for $100 a year) alone, but it's a fixture of the cloud storage world. It's got wide-spread app integration, unlimited uploads from desktop and mobile apps, an intuitive interface, and a proven track record. And you probably already have it. Then there's the added bonus of free space (up to 18GB) for referring friends (or yourself with fake emails on every device you can find) and the promise of some sort of magical Mailbox integration down the line. It's not the hottest deal out there, but it's tried, true, and bullshit-free.