Well, I have external remote drives connected to my router. Most routers only have 2 USB ports though. Still, most will handle 2TB USB drives, and the newer ones with USB 3.0 I think can handle the 4TB drives. If you have than many external drives and they are SMALL, cheapest solution might be a router that will handle USB drives. Can be set up as Media Server or FTP sites. Yeah, transfer can be slow, 130Mbps seems to be the fastest I've gotten on a 1GB wired to the router connection. Video files are served up fast enough to wireless devices like the Home Theater and iPads.
I also believe but HAVE not tried, that a USB hub can be places on one of the USB router ports. Right now I have a 1TB USB drive attached and it handles anything we need to place on it. Occasionally I put on another USB drive to save away sporadic system images.
Only downside I see is lost data if something goes wrong. I've had one USB drive die on me.