Amazon S3 has become the de facto standard for object storage. In one of our projects we had to evaluate various storage systems compatible with S3 API. The following is a list of storage systems that have Amazon S3 api compatible interfaces.
- Openstack swift
- Basho riak
- Red Hat ceph
- *Rackspace cloud files
- *Google cloud storage
* - managed, ` - licensed, rest - open source
While the advantages of using S3 is obvious, others (non-managed ones) have the same lifecycle of hugging hardware + software learning curve + ops maintenance cycles.