Now you see me, now you don't.
How To: Build Your Own Rather Impressive Invisibility Shield

This is a video of Youtuber Randomonium discussing, building, and demonstrating his homemade invisibility/distortion shield constructed using sheets of lenticular lens. For those of you unfamiliar with how lenticular lenses work, he provides an explanation and diagram at around 2:30. Randomium estimates the cost of building your own shield to be around $130, which, I think we can all agree, is a small price to pay to never lose at the hiding portion of hide-and-seek ever again.