@Dylan, my answer is already in your comment. 😀 I mean, they're essentially servers the size of a large grapefruit.
My answer depends on how you define a NAS. In the end, they are all mini PCs or servers with a certain form factor. But to give you an idea, I’ll describe my setup. I distinguish between my home network and my homelab.
Home Network
My home network is used by my family, mainly for file sharing and backups. The cornerstone is a rock-solid Synology NAS DS1520+, which I use for local Office 365 backups. Additionally, I back up my photos from my NAS to the cloud, so all my files are stored both locally and in the cloud. Before this, I had a DS414, which ran 24/7 for over 10 years.
Homelab
I have a separate network segment for my homelab (Mikrotik 2.5GbE & 10GbE network). All devices in my homelab run Proxmox in a cluster. My Aoostar WTR Pro serves as a NAS/storage (HexOS) and Proxmox Backup Server.
Additionally, I have:
Intel NUC 11 Pro → Runs Windows 11 and macOS VMs, stays powered off when not in use.
Shuttle DL30N (Intel N100) → Runs Docker apps.
Lincstation N1 → Test server, including a second HexOS installation.
I recently ordered a Lincstation N2, which I plan to use as my primary HexOS server. This will allow me to repurpose my Aoostar WTR Pro as offline storage, activated only when needed using Cron jobs and Wake-on-LAN. The Lincstation N1 will then become my Proxmox Backup Server, allowing me to quickly restore VMs or Docker containers when experimenting with configurations that don’t work as expected.
All of this is housed in 10-inch racks. I’m a big fan of small form factor devices that strike a balance between maximum performance and minimal power consumption.