Over the years, the guys from novelty shop Vat19 have made a bunch of giant-sized things inspired by stuff they sell. Among their ridiculously oversize creations are a room-size air hockey table, a 250 lb. gummy pizza, a beer pong catapult, and a pool-sized bath bomb. They also made a gigantic bouncy ball.
Vat19 shows off some of the fun things you can do with these glow-in-the-dark magnetic construction spheres. Each pack comes with 216, 0.5 cm diameter neodymium balls, but if you pick up 24 packages or so, you can build yourself a magnetic lightsaber, just like they did.