I use Armory client for home use. I keep most of my coins as offline paper and SD card backups (I built the client for my Raspberry pi and it seems to work well for this). I then use my watch-only addresses on my online computer. I know there is a bit of "magic" involving chain codes going on when I request my client to determine the next receiving address from my watch-only copy. My question is this: is there a version of this as a headless standalone program that would take a watch-only address, load it and have it generate receive address deterministically and on demand (say through JSON-RPC or similar protocol)? I've scanned over BIP 0032 and I'm sure I could hack something together myself, but I certainly don't want to reinvent the wheel.

Edit: please forgive me if I butchered any of the vernacular.