Seagate has introduced the Exos M series, a range of enterprise-grade mechanical hard drives available in 30TB and 32TB capacities. The two models, the 30TB CMR ST30000NM004K and the 32TB SMR ST32000NM003K, each offer a minimum of 3TB per disk and use a standard 3.
Do you know about tape backup systems for consumers? From my (brief) search it looks like tape is more economical at the scale used by a data center, but it seems very expensive and more difficult for consumers.