In search of the holy grail of home servers

ATM my home server runs Windows 7 Ultimate (trial mode till end of December) and I am researching free alternatives like freenas, openfiler, ubuntuserver, freebsd. Need this machine to support administration via web gui and provide following services for me

1. file sharing via SMB/Samba
2. torrenting with webgui
3. http web server
4. webdav
5. vpn
6. upnp/dlna media serving to multiple upnp/dlna players simultaneously
7. continuous data backup (windows live sync style, propagating changes between machines immediately, rather than overnight)
8. advanced disk/RAID management, described below.
9. seems that vitrtualisation is high on my list too.

Found this thread discussing freenas and drobo functionality, and thought that this post decsribes my needs too.

I'm also looking for the holy grail of RAID solutions and really hope someone can come up with or find something. I want the following features: REQUIRED: - Redundancy, allowing for at least 1 drive failure - Mix and match drive sizes WITHOUT being limited by the smallest drive (and thus wasting space) - Ability to add drives to increase capacity - Ability to replace drives and increase capacity - NAS functionality, accessible via a Windows share - Ability to create multiple partitions, with respective shares (or one large partition with multiple shares mapped to folders on the NAS? Who really cares about the "internal" file structure..) PREFERRED: - Performance that isn't terrible - In my case, fast enough to steam 1080P over ethernet - Minimal data capacity loss due to parity (< 50% - Else I'd just mirror.) - "NTFS" Volumes larger than 2TB (Not sure if this is possible via a share.. perhaps "Emulate" NTFS and actually store on a file system with larger volume capacities to achieve this? I could care less if Windows reports my remaining space correctly, as long as the NAS would.) - Software-based, so I can also use the box for other purposes.

I already run freenas in virtualbox on my server with bridged network interface on my server, and it appears as separate machine with web gui on my network. I already see some of the drawbacks of freenas, like no webdav, vpn, virtualisation (the kind that allows me to test freenas in VM like I do it now).

Downloading freebsd, openfiler and ubuntu server to install as VMs too and give ‘em a try this month.