I've seen a few places touting the merits of "bulletproof coffee," so I thought I'd try for you. Basically, the idea is that the combination boosts energy and helps you lose weight. By adding a coconut oil combination along with grass fed butter or ghee, you change your metabolism.
It's a fair amount of work to make a cup. Grind the beans, do a French press, measure out the oil and ghee, whip to perfection in the blender...you get the idea.
However, if you're committed, it does produce a rich coffee reminiscent of buttered toast or a really good latte. I do think it gives a slight bump to energy and metabolism. Nothing major for the work involved; but if you are looking for an edge, this is it.