However, it would be great if this could work with Chrome as an extension. You'd probably want to avoid writing a native plugin for it, because that would require compiling and would be a headache for managing the extension (and gpg versions, etc). Instead, one thing you could do is setup a daemon that the extension could talk to, bound to localhost. But then you'd have to manage authenticating Chrome to the client, etc... perhaps I found something to tinker with over the weekend.