Cloud Storage

Microsoft Azure Storage ServicesLarge-scale cloud storage service based on the Azure PaaS.
DropboxOnline file hosting service offering cloud storage and file synchronisation.
BoxOnline file sharing and content management service focused on business.
Amazon S3Scalable online file storage service with on-demand pricing structure.
ownCloudOpen source (GPL) client-server software for hosting on-premise cloud storage solutions.
SpideroakPrivacy focused online backup service.