This is a simple one for most of you, but I found someone asking the question "How do I dump messages from bootstrap.js" on stackovercrap so I thought it would make a good topic to quickly blog about.
Bingo! Give the page on nsIConsoleService a re-read. There is a code example on the top of that page that you can use to get a console service, then the page describes it's various methods, such as logStringMessage. You can use the logStringMessage method in window.dump's stead.
The window.dump page also mentioned Components.utils.reportError which can be used for logging error messages to the Error Console.
Services.console.logStringMessage("this is a console message, look for it in the messages tab of the Error Console.");