LEGO artist Jason Allemann has built this continuous loop LEGO marble run. It expands on one of his previous designs to include an elevator so that it can run continuously as well as an alternator module, which splits incoming balls in alternating directions. It's a neat design and very interesting and all that, but I can't get over his LEGO storage room. That's the stuff dreams are made of. Six year old me would've planned a Mission Impossible style heist just to get in there and steal it. In unrelated news, I need to run to the store to buy a ski mask, a harness, and some rope.
Keep going for the full video, along with his original LEGO marble run design.