The StorSimple devices have been a excellent way for customers to connect their on-premise storage to the cloud, to exploit the scale and cost efficiency that brings without radically changing their storage infrastructure. It enables offsite snapshot backups and a cloud DR solution in a single appliance that's easy to install and integrate with existing storage and backup solutions.
Coupled with support for applications like SharePoint (through remote BLOB storage) and it makes a compelling solution for anyone requiring additional storage (everyone!), but are torn between the on-premise and cloud requirements.
Microsoft have now announced a new version of StorSimple which remove the need to have a physical appliance - and therein the biggest cost - by enabling StorSimple to be deployed on premise as a virtual machine (in either Hyper-V or VMware). As a virtual array, it can present local storage as either file shares (NAS) or iSCSI targets, making it interoperable with virtually any server, storage solution or backup application.
Most importantly though, it retains the data tiering capabilities of the physical appliance, moving "cold" data to the cloud, ensuring your comparatively expensive local storage can be used for the most important data. Snapshots are also sent to the cloud, ensuring rapid disaster recovery in the event of a data centre failure. In addition, when configured as a file server, users can retrieve their own backups in a self-service.
Microsoft see this as a storage solution for branch or remote offices, but I would add small and even medium sized businesses to that list, particularly those that are struggling with legacy file servers and older SANs.