Vista introduced what they call UAC as a measure to prevent unwanted software to install or run... But I think it's a failure because it's more of an annoyance than a security measure, and you just end up clicking ACCEPT every time because it justs asks you for everything single you do. I can't say how much I hate this, because a 3 clicks task in XP is now turned into a 10 clicks nightmare.
My point is that asking for a password, ONCE IN A WHILE is taken more seriously than a stupid click every minute.
The best example I can find is SUDO: It asks for a password once, the first time you use it in a session. I think it's enough, I don't get annoyed, it's secure!

I was about to try to remove that password thing but the way some people here have brought the subject has made me think, thanks
