If you're already using Panamax, look at their Blue Bolt stuff. It'll do all the remote power "stuff" you want to do anyway. Plus you can log into IP cameras remotely without using any type of remote desktop software. I don't think you need a PC on site for what you're talking about.

Look at full control systems, starting with Control4 and Elan g!. All the remote programming is already part of the system. Remotely controlling the system via PC is already part of the system. If you just wanted to trip a relay to trigger a power strip then that is already part of the system.

I think the more you look the more you're going to find a much more "elegant" solution to what you're trying to do. You've got the right idea. I remember reading about CytexOne (big Control4 dealer) putting together a rack for a job on the other side of the country. They included a VOIP phone mounted to the front of the rack. It was an extension on their phone system. The customer could just pick up that phone an it would connect to their tech support. Then there was an IP camera with about 20' of cat5 rolled up inside a rack drawer. The customer could walk around the rack and the tech could look at exactly what they were talking about.

You want to see some REAL remote service, check out CytexOne's Atlas system. I've never dealt with it, but it's a very cool idea.
[Link: cytexone.com]