I think that a better option would be to use a cheaper network device with third party firmware.
Check out OpenWRT or DD-WRT or Tomato, which are Linux based. You could get a nice setup if you can find a good enough device. If you check out hardware databases for those distributions, you'll be able to find some pretty interesting devices. With little bit of searching, you could end up with a router with gigabit ports, 64 MiB of RAM and USB ports too. After that, since there's USB, a powered hub and external hard drive could solve any problems with storage space for packages. Plus plus you could add a large amount of other devices such as sound cards, bluetooth radios, webcams and so on. Also it seems that third party firmwares offer much longer support for devices than official firmwares.
Since you mentioned Linux and BSD, you wouldn't have too much problems with set-up, if you're used to working with console.
Also you will be able to save money on electricity and on device itself.
Please note that when writing this answer, I paid attention to the part of the question where you mention home network. I think that even with free firmwares, most home network devices won't work too well with hundreds of computers all sending data at their maximum speed.