It's pretty much in the same boat as tatting, popularity-wise. Needle felting is an art where you'll have an amount of wool roving that you gather up into the shape of your goal object, maybe roll it around in your hands a little, and prick prick prick with a barbed needle, felting it until it's firm and all the fibers are tangled. It can be very cool, and some people are absolutely amazing.
I learned about it a while back and whilst venturing in a foreign area of JoAnn's, I discovered that they carry needle felting supplies! Ecstatic, I spent about $40 on supplies: a little brush thing so you can prick through the entire object, a set of needles, and black, pink, and blue roving. That night, I made a little figurine and a poodle. My brother seemed far more excited though. I ended up giving him all of my supplies, and now he does it.
Needle felting just isn't my thing, and that's okay, tatting is! Here's a little heart that I made <3