A network attached storage, or NAS, is a micro-computer that sits somewhere you’re not. You access it as you would any other network drive, and as such, it’s simply a storage solution. Plug it into your wireless router, and you have wireless access.
I bought myself a 107+ and a 1TB SATA drive. Connection of the two was easy, as no cables were involved (by the way, the 1 in 107 refers to the number of drives you can add, the 7 to the hardware revision, so a 407+ is a 107+ but with room for 3 more drives).
You’d think that was it; 1TB wireless storage (delicious). It’s not. Because the Synology is a computer with firmware from a company that does little else than implement user suggested features, the NAS is SSH accessible, it’ll turn on and off for you on a schedule, it’ll automatically backup stuff, it’s Time Machine compatible, it’ll broadcast your music library, it’s PS3 compatible, and it’ll even download episodes of Lost for you. All that, right out of the box. Best gadget I’ve bought.