I've been a big proponent of Thecus NAS here and they've saved my bacon a few times with hard drive crashes and its redundant hdd capabilities. If you're using one too and are on a Mac, then Thecus has a new update out that will backup Apple's latest OS. Thecus's latest firmware update now supports OS X 10.7 that also brings AFP 3.3 to the fold with improved performance and backup with Time Machine.
09/06/2011- Thecus’s new firmware V5 is here with support for Mac OS X 10.7. In addition to the obvious superficial changes implemented in Apple’s new system, such as the Launchpad and full screen apps, Apple also upgraded their transfer protocol to improve performance with Apple Filing Protocol (AFP) 3.3. Optimized to connect over AFP 3.3 and backup with Time Machine, Thecus NAS are ready to take advantage of these latest advances from Apple.