I like the concept of implementing the "waiting" function of responding to a cheat code as an asynchronous promise-style callback. I think this should be used more often in event-driven stuff, even when it's not explicitly "asynchronous" as much as it is a conditions-based response.
I went ahead and made this[1]. The implementation is a little different from the way you do it, and it uses jQuery to create the events, but it supports sequences of click events using jQuery selectors like in my original comment, other events could be added without much effort.
The implementation is not at all as neat as the original, and i haven't done thorough testing, i just had an idea and tried it out.
Any hints on easter eggs on the site that you don't provide instructions for? I tried your name, the project name, etc.; disappointed there wasn't more to discover.
[1]: http://craig.is/killing/mice