This was one of those times.
I don’t know what reminded me of it, but I suddenly remembered an image I’d seen on the interwebs years ago about how to make a ninja mask from a black t-shirt. A quick Google search later and I’d found the original. (Click for full-size instructions)
Since I had no one there to walk in and ask me what the hell I was doing, I absolutely had to “get my ninja on”.
Now, since I’ve provided you with the necessary instructions, you may also “get your ninja on” and join the silent horde of TGNP (Techno-Geek Ninja Princess?). If you do, post a link to your picture in the comments!