1. They had joined a Gordian knot of vans, taxis, and automobiles that was inching forward at a pace that had set that little muscle in his jaw to knotting and unknotting. BNC
2. If Gorbachev expects to untie the Gordian knot, he has over-estimated his powers. WASPS
3. Homelessness in the inner cities has become a real Gordian knot. CIDoI