Loom of Fate
As seen in: Wanted
Forget the Matrix of Leadership, the Blade of Unicorn or even the Triangle of Light. The most eye-rolling, archaic MacGuffin of all would have to be the Loom of Fate, which would have sounded great if it had transpired to be some kind of code word for a missile strike, but alas, it is in fact a loom. A loom! Not since Sleeping Beauty has a textile machine taken centre stage to the extent it did in Wanted because, here, trained killers rely on this loom to tell them who to assassinate next. But there's a twist: Not only do the relatively smart people murder everyone that the loom tells them, but when they all find out that Morgan Freeman has been tampering with the names for profit, Angelina Jolie kills herself and all her fellow hired guns because, again, the loom told her to.