Yeah, its a pretty cool idea.

I've actually seen this concept before though, in one of the business magazines I get, oddly enough.
It was either BusinessWeek or Forbes (can't recall which one) that featured them in their little "style" section they run periodically. I can't recall which company the belts were from though I'm fairly certain it wasn't this guy.

Here's another group that makes them:
http://www.jiro-belt.com/

But I do like the idea. Not to get all treehuggerish but obviously reusing these is a lot healthier for us all than dumping them in a landfill.