As the GM of a group of creative people I'm used to seeing some crazy ways to use stunts. Here's just a couple.
The party's main warrior, an Avvarian Hillsman named Nidhogg, was faced with finishing off an ogre but required help from one of the rogues, the Dalish Elf Montiech. Nodhogg inflicted heavy damage on the ogre but it needed to be finished off. Montiech used skirmish to leap off of Nidhogg's shoulder, moon flip and land on the ogre's back, and deliver a lightning attack to its temple regions, killing it.
The dwarven rogue of the group, Givvec, was faced with an angry Hurlock on a battlefield consisting of several burning caravan carts. After a few traded blows Givvec got the upper hand and delivered a mighty blow along with pierce armor (1sp from being level 2) and lightning attack. The hurlock was pinned through the stomach by Givvec's blades into the side of a burning cart. I did indeed roll to see if the hurlock could get off, he didn't, and so burned to death pinned to the cart.
There's a lot more than that though, my friends can be very creative with their kills.