Netgear ReadyNAS DUO
Absolutely works perfectly with my Netgear ReadyNAS Duo, and to be honest with you, I have so many other things I can do with my NAS compared to buying a silly over priced time machine.
For starters my nas:
1. Has two disks - mirrored - so if one drive fails, I do not loose my data. The Time Capsule does not.
2. Has a Linux operating system in it - that I can console into to perform file operations and all kinds of fun stuff that can't be done with a closed system like Apple's.
3. Has a built in bittorrent client for downloading torrents - which means I don't have to leave my computer on.
4. Has a built in newsgroup client for downloading binaries from the newsgroups - again keeping my computer from having to be turned on.
5. Supports a UPS on one of the USB ports so it safely shuts down in the event of a power outage
6. Supports backing up to a USB drive automatically (attaches to the front port)
7. Can attach 2 external USB devices like a printer or a hard drive for additional capacity on the network.
8. Supports all major network sharing protocols including SMB, CIFS, and AFP (Apple's network protocol)
9. Has user accounts and home directories so I can give the room mate storage on the network without having to give him access to my files, even has quotas as well.
10.Has a very awesome support community that is always willing and able to help.
And last, but certainly not least, as new wireless technologies evolve, I don't have to buy a new $500 dollar time capsule to get the latest stuff, I just replace my router.
With that said, there is one thing you can't do with the NAS, which is - store our iPhoto library on it, but I believe Apple also DOES NOT support storing the iPhoto on the time capsule.