Mega (www.mega.co.nz) is a cloud-based storage service and successor to MegaUpload. Launched earlier this year, the web service has released apps for Android and iOS, but the company has now confirmed that a Windows Phone solution is well on the way. The only problem is you won't be able to download it until 2014.
The service supports encryption on the client side with an "advanced AES algorithm." The company cannot decrypt or access files stored on the service, taking no responsibility for content uploaded by registered accounts. Both free and paid data plans (three tiers) are available, depending on just how much you wish to store in the cloud.
Here's a copy of the email response from the support team at Mega:
It's positive to see such a massive brand supporting Windows Phone so soon after competitor platforms. Do you use Mega and are eagerly awaiting a Windows Phone app?