I'm concerned about humidity. I want to get everything as close to perfect for our ball as possible

At the moment I have the enviroment and temps working as I want and I'm happy with that, but I have little "control" over humidity. While we don't have much of a problem with humidity I would still be happier knowing it was monitored and controlled. I'm about |<-->| this far from buying a herpstat II just because it logs temps and will email you if there is a problem, and I can set it up to view temp conditions online any time I want...yeah, yeah I know I'm a geek.

Anyway is there anything similar for humidity control? As in a control system that monitors the humidity and then can mist as required or somesuch to keep the % where you want it? I have looked online quite a bit, but I'm not sure of all the best places to buy equipment so I might be missing it. I can find misting systems, but they are all on, or off. I'd like a system where I can just set it to 60% and not have to worry about it, and crank it up during shed and so on.

Thanks!