This is one of those instances when I wish I owned a small digital camera. That way I could snap a quick better-than-a-thousand-words illustration image. The diopter mount blends in so well with the black camera covering material that people think it's a cool OEM attachment of some sort.

If you do give it a try remember to clip the four corners of the plastic at a 45-degree angle to reduce the chances it'll get snagged on your clothing and unknowingly pop off, thus losing a nice diopter lens. As mentioned though, that's never happened to me.