Action & reaction. Angles and speed. Momentum and inertia. Pinball is a game of physics. So is Portal. And that's what makes this homemade Aperture Science pinball table so great.
Reddit user iliveon built the working table with friends and says the goal is to get a pinball stuck in each portal. It's clearly a labor of love and could only be improved by having GLADoS making fun of you as you played.