Had to pass this along. It's an insane price.
I can remember seeing an Ethernet miniboard in 2001 for $129.00 and thinking, gosh how cheap can a component like that get?
In combination with my pending switch to BACNet communication, opens up Vault-OS to all kinds of crazy intelligent nodes and devices. If you think about what other stuff is coming onto the market like image and speech recognition chips falling into surplus in the mobile phone markets ... you are really seriously looking at a science fiction networked system for your vault the likes of which was only in Hollywood movies twenty years ago. There is supposedly a mobile phone display circulating now on EBay with intelligent VT-100 serial commands, so even a small terminal in Vault-OS could display floating 3D diagrams of maps and layouts in real time as fed to it from the server! "Fire detected in generator room" and it is marked in BACNEt as a diagram receiver, so it shows you exactly what triggered the alert on a little mini map! You know even before you get there it's on the battery bank, so you grab tools to suppress an electrical fire!
The amazing thing about raw socket frames for Ethernet is that's it is two-way and basically asynchronous. Anything can talk when it wants and anything can receive. Imagine a raw frame network as a whizzing stream of mail going by - all the device has to wait for is a tiny niche to insert it's traffic before dispatching a BACNet packet into the rushing flow of messages circulating everywhere. The address on the packet marks it to a certain IP and that's where it gets plucked out of the stream.