A NAS is my preferred choice, over a PC. Smaller than most any PC I could cobble together, lower power, quieter, unassuming. They even make WiFi-equipped models.
Which just made me think of something- if you are concerned about network security and isolating your backups, what's to stop you from keeping the NAS unconnected to your WLAN, and at time of archival, explicitly establishing P2P WiFi connections with the NAS from the client PC...
Which just made me think of something- if you are concerned about network security and isolating your backups, what's to stop you from keeping the NAS unconnected to your WLAN, and at time of archival, explicitly establishing P2P WiFi connections with the NAS from the client PC...