What are some alternatives?
When comparing Windows Home Server and unRAID Server, you can also consider the following products
FreeNAS - FreeNAS is a storage operating system strong and robust enough to meet the needs of enterprise level businesses.
OpenMediaVault - OpenMediaVault is the next generation network attached storage (NAS) solution based on Debian Linux.
SnapRAID - A backup program for disk arrays. It stores parity information of your data and it recovers from up to six disk failures.
Rockstor - Rockstor is a free and open source NAS (Network Attached Storage) operating system.
NAS4Free - NAS4Free is the easiest and quickest way to install an Open Source free NAS server. From home NAS to enterprise network storage, NAS4Free is trusted by thousands of installations every day.
Amahi Home Server - Amahi is a media, home and app server software known for its easy-to-use user interface. Amahi has the best media, backup and web apps for small networks.