It's the Valco Trimode Twin. First, it's a double jog stroller. Then, you attach the toddler seat at the front, so you've got a place for 3 children to sit. Theoretically, it looks like you could then attach the Hitch Hiker Ride-on Board, so an older child can stand and be pushed around as well. However, I'm guessing this might be pretty heavy. 4 children, 1 stroller, might be asking a lot. Speaking of A LOT, did I mention how much this chariot costs? With the toddler seat, a whopping $799!! Yikes!
So, way to go stroller inventors! Keep 'em coming!