Yeah, interesting story, this one. I'd seen the Kickstarter capholder a few days ago and though, wow, this guy could just start producing now on Shapeways, no need for Kickstarter here. Then I saw this blogpost and thought, ah, he's done it! And I tweeted about it.
Then I checked back and realized that there were two different persons doing the KS and SW versions, and tweeted about that. Got a tweet back from the SW designer, saying that the Shapeways capholder is not a copy of the Kickstarter one.
Anyway - I completely agree with Tom's final statement...
Great idea. Shame it's limited to a single cap diameter. I usually have two or three cap sizes one me (any combi of 49, 55, 67 and 72). Right now all my caps are attached using an elastic string. I've been thinking of a cap holder too but using a different principle which is not that size dependent. It's on my fairly long "to design" list.