There is a good chance the data on your computer was downloaded from a FreeNAS-based server at some point. FreeNAS, a storage-specific operating system derived from FreeBSD, is a timeless classic that gets better with age. iXsystems, a seasoned server and open source storage builder, continues to develop the software, making improvements to performance, reliability and ease of use.
Most of iXsystems' products are traditional rackmount storage servers. The company specializes in custom builds with a large number of options available, from 1U single-core configurations to 4U eight-node systems. It also sells a number of preconfigured systems, the type you see in datacenter pictures with lots of drive bays that light up like a runway.
The FreeNAS operating system is open source; that's where the free portion comes from. Anyone can download the software, burn it to a disc and install it on a system. Since the software is free and works with a wide range of PC hardware, a great many storage enthusiasts have opened it up, modded it and contributed to the project. iXsystems took over development several years ago and continues to develop it today. With so many using the software on home-built machines, iXsystems saw the opportunity to leverage its experience in a low-cost volume server.