I've made a number of these balls-o-caps over the years, but I always tied them together with soft wire. I've recently mastered tying them up with string. Here's a few of the new ones.
In the Acorn-Bamboo article I mentioned Poly. That excellent shareware program shows 157 shapes. Crystallographic Polyhedra by Dr. Steffen Weber also shows several really cool ones. It's under the Wireframe Polyhera heading on his homepage jcrystal.com