Very interesting bit of arcane knowledge I stumbled across. After I already bought a plug'n'play I2C controller for $68 USD.
Almost all modern PCs with recent graphics cards have a built-in I2C controller right now, ready to rock. I2C is rapidly becoming the world's simplest input/output controller for embedded applications with nothing more than serial commands.
There's a Vault-OS version coming in .NET, for sure, before the end of this summer. I am working on the DOS real mode version a couple hours a week but I've been tinkering with the .NET version almost every night. It is starting to look pretty awesome. Screenshots coming soon for both versions.