a button that can only be clicked once, EVER

Question

as the title said i would like to create a button that says "available" and once any one clicks it it turns to "unavailable" for all future users any ideas ?

note : its for a school project, nothing fancy or even secured, just trying to prove a point

sorry for being vague for some, all i am trying to do is to create an article in my joomla website with a button that only the fastest user can access and click, thats it i am not worried with security or even cheating attempts joomla articles can have php js codes among others added to them

Answer 1

Quite complicated, really. Generate button by JavaScript to prevent people without JavaScript from clicking it uncontrolled. Keep a comet server so that when one user clicks it, the change is instantly propagated to all other connected clients, and the button is removed. Afterwards, do not authorise the generation of the button, for any new users.