GREENVILLE, SC -- It looks like a tire that's had its sidewalls torn off, but the Michelin Tweel is actually a combination of a tire and wheel, and it's designed to run without air. Using flexible spokes attached to a flexible wheel, the Tweel "envelopes road hazards" instead of bouncing off them, according to Michelin. While the Tweel is in production for uses on several Segway vehicles, it's still in the testing stage for automotive use, where speeds are higher and the loads are heavier.