Dynamic text in the scene

So I want to create some UI that is rendered “in world” instead of just onto the screen. In particular, I want to achieve an effect similar to this: http://wakeupandsmelltheashes.files.wordpress.com/2012/05/tom-clancys-ghost-recon-future-soldier-4.png. I thought maybe I would use a text render component, but it seems like those aren’t dynamic. I am also wondering if I could use some sort of dynamic material to achieve the effect as well. Any thoughts? I could really use some help.

PS: This can be either a BP or Code solution, though I would prefer a BP solution.

But can I change that text dynamically?

OK, I can confirm that the text can be changed dynamically. I am trying to accomplish this within my weapon blueprint, but I cannot find a way to get the input event to work. What I have is an input for StartFire, and I have connected that to the text change node, but it never fires for some reason. Should I be doing this in a different class?

You have to have Inputs enabled for your player controller.
https://docs.unrealengine.com/latest/INT/Gameplay/Input/index.html

Alright, so I was able to get core functionality working, but there is one other problem which isn’t really related to the original post, but I will post it here anyways, just in case. How do I extend the functionality of an inputaction from blueprints? Does the inputaction code function need to be blueprintable so I can just call it first then call my stuff?