I'd try out Box.com. I've been using them to store eBooks for my website and they have a ton of awesome features that make storing and sharing your content a breeze.
They obviously have paid options, but you can get a ton of storage with the free version and then just update it later if you ever run out of space. I give them two thumbs up because they've made storing and sharing files really easy for me and that's helped my business out a lot.
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