Cancel or allow?
Windows Vista includes User Account controls which purport to warn the user whenever anything happens which could theoretically be dangerous. This feature has been widely reported as being, shall we say, over-zealous, to the point where many users are likely to switch it off because it’s too intrusive. But then, how would you be warned if bad things really were happening? Apple have gleefully seized on this dilemma and made a new one of their Get a Mac adverts about it:-