I have a Moldovan daylily called Gulliver's Travels that was never registered. While it has been distributed quite a bit, the non registration has been a bit confusing. There are also duplicate names using a prefix that can be a little confusing. Spacecoast, Small World, Stone Palace, etc.
I use White Eyes Pink Dragon quite a lot, and had a seedling that I called White Eyes Purple Dragon, until Jamie registered one with that name. I'm glad now that I never called it that in front of anyone to avoid that confusion. I really don't want to give them names unless I register them, especially now that it happened to me. That is part of the reason why I intend to eventually get rid of all my named ones, so that everything in my garden is "seedling"!