That's a great idea. The downside is I'm not sure you could just use on of the out of the box preconfigured turnkey appliances. You would have to do a lot of the configuration yourself. It's definitely doable though.
So basically a banana pi runs standard ubuntu/debian out of the box - that is pretty cool.
On a similar note, here is a vpn solution for a rapsberry pi. http://www.pivpn.io
I also saw this: http://www.instructables.com/id/Ultimate-Pi-Based-Home-Server/
So definitely worth thinking about. Probably use a lot less power than a standard computer as well.
Sam Taggart
CLA, CPI, CTD, LabVIEW Champion
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