I'm after a NAS box to use at home but I'm confused by all the options out there and can't figure out if there is one that actually meets all my needs... Here's what I'm looking for: 500GB, expandable via USB port(s). Print server. Secure access via the interweb so I can share contents with friends & family in far away …
Buffalo has what you need
Buffalo Terastation Live
Be sure to also check out Terastation.org for all your hacked firmware needs.
Try the QNAP NAS boxes
I have had two of them, one a single-drive version and now I have a dual-drive version.
They have the ability to do all that you require, including a media server and a BitTorrent client. It has a Gigabit Ethernet connection, and USB ports at the front and back.
If you get the single-drive version then when you want to add another one, you can just buy a second NAS box and RAID them across the LAN. This is not something that I have tried myself but QNAP claims that this is feasible. There are updates available on its website from time to time which add new functions or fix some bugs. It runs on Linux so is open and extensible.
I'm very happy with mine, although I use it mainly as a back-up device to my PCs connected to the LAN.
You'll be wanting the QNAP TS-109. It does everything you want and more. In addition to gigabit ethernet and 3xUSB2 it also has eSata for expansion and can RAID1 onto it. If you also want NFS and AD then go for the Pro version. SlimServer is pre-installed for free. Check qnap.co.uk for more details, it's the dogs.
There seems to be very little at the home, hobby end of the market. Which is surprising. I believe Lacie has something new. A 3.5" disk enclosure and NAS bits shouldn't really be more than 100 quid but most of the offerings are more like 500 quid.
There's a lot of gotchas in this area. Avoid anything that requires drivers on the client PCs. It should support Samba, windows, macs, linux out of the box and ideally use FAT32 or NTFS on the drive.
Have fun with a Linksys NSLU-2, Unslung software and a USB hard drive. Cheap and hackable. Linksys should really combine an NSLU-2 with a WRT54G Wifi router and a 3.5" disk enclosure.
The ReadyNAS NV+ from Netgear (who bought Infrant, the original company). It does all the things you need, including running the squeezebox.