Jen, an Instructables community manager, has combined regular ol' fresh-squeezed lemonade with capsules of activated charcoal to make her Black Lemonade.
Refreshing, and goth af.
She writes that activated charcoal has several health benefits but, (from what I gather from commenters on the recipe's page) not everyone can tolerate it. So, please, don't serve this to anyone without their knowledge. (Sorry, the mom in me totally just came out.)
Still, it looks really cool.