I've been debating creating my own AquaController type device since I set up my tank. I did some poking around at work today, and it seems someone might have already done so. This setup uses a Linksys wrt54g wireless router as the controller with a custom firmware on it. Linux + Reef = dork paradise!
http://bytality.com/wrrc/index.cfm?doc=Wireless%20Recycled%20Reef%20Controller
http://bytality.com/wrrc/index.cfm?doc=Wireless%20Recycled%20Reef%20Controller