Can I install an app built for iOS Simulator onto a second simulator?

I built an app and ran it on the simulator on my Mac (Xcode 4).

I'd like to copy the built app onto a second Mac, also with Xcode 4, just to run the app in the second mac's iOS simulator.

That is, I don't want to have to build it on the second mac, just run the app in the second simulator, for presentation purposes (second Mac is connected to big screen in conference room).

I see the app in Debug-iphonesimulator folder, but how to get that onto the second sim?

The iPhone simulator stores its apps in ~/Library/Application Support/iPhone Simulator/<OS version>/Applications, each in a folder named with a GUID. Browse the contents of those folders to find your app, copy the GUID-named folder to the corresponding Applications folder of the other simulator, and you should be set.