If it's purely for backup, take a look at Google Cloud Storage. Pricing for Coldline Storage and Archive Storage is pretty low. - Source: Reddit / about 1 month ago
Zadara Storage - Enterprise Storage-as-a-Service Solutions (STaaS). On premises or in the cloud. Fully-managed 24/7. Pay only for what you use. Leading companies worldwide trust Zadara Data Storage. Proud to be the best cloud storage option
Google Drive - Access and sync your files anywhere
Vultr Block Storage Vultr - We are simplifying the cloud. One Login, 9 Countries, 16 Cities, Infinite Possibilities.
Dropbox - Online Sync and File Sharing
VMware vSAN - VMware vSAN is radically simple, enterprise-class software-defined storage powering VMware hyper-converged infrastructure.
ownCloud - ownCloud is an open source project enabling businesses to host their own cloud storage while maintaining regulatory and compliance needs.