Yeah...I think everyone is just having some fun with this thread, GB.
However, to quote the initial post:

"I like to put a rubber band around the shell of the hub as I start to build a wheel. It's not so much so that it will shine the hub like those old leather things. It's more for the curious look of something without a joint in a seemingly inaccessible place, seemingly unless you know how wheels are built. But rubber bands don't last more than three or four years before they break. What is more permanent that I could use?"

I still go with the O ring idea. However, a rubber band will stretch over the hub flange. An O ring stretches some, but not as much as a rubber band. So it might require a pretty large O ring on a large flange hub, etc.

But a red or green silicone O ring might look nice. If that's your thing, that is....