i just tested starting a new server with flight mode on my pc and with localhost were able to connect without any problems.
so as far as i know its not tied back to their infrastructure
edit: says on the site: "You can run your own server independently and no traffic is relayed through a third-party server." (http://www.neorouter.com/products-nrfree)
Run NeoRouter on your PC. That's it. You can access your files like they are on the local network. Use DynDNS if you don't have a static IP. You won't need a new computer or dedicated hardware - it runs on anything.
I've used NeoRouter quite effectively as a Hamachi alternative.
And if you want to go open source, check out freelan. Haven't tried it myself, but seems promising:
Neorouter. Lets you set up your own VPN with a server you control in the office. Remote laptops become encrypted peer-to-peer clients that are part of your intranet. Anything they can do in the office can be done remotely. Setup is dead easy.
I'm a huge fan of NeoRouter, and I'm kinda surprised that it has been under the radar. It lets you easily set up your own VPN/remote access with your own equipment. You install the server on a home desktop PC, and the clients on your remote devices (laptops, etc.), and port-forward one port number to your server from your router. That's it.
Basically gives you an encrypted local network that runs over the internet. Whatever you can do with a local network (VNC, remote desktop, file sharing), you can do with this over the internet. It's peer to peer between clients once connection is established. Doesn't require a 3rd party server to transfer data (their server just provides IP addresses to establish your network).
I've used this on overseas trips with great success, and I get a nice home VPN to use from the coffee shop. It has plugins for VNC, a proxy, FTP, PuTTY. Works on Windows, Mac, Linux, Android, and several routers (I've only tried Windows and Linux). Oh, and it has a portable version so you can connect to your VPN from any PC using a USB key. The free version works great for almost all uses, up to 256 licenses.