UUIDs are only unique if you generate them...
We had an internal discussion recently and the upshot of the discussion was that it turns out that some distributed component on the web appears to have used the UUID of a sample COM component.
I wonder sometimes why people do this. It's not like it's hard to run uuidgen and then copy the relevent GUIDs to your RGS file (and/or IDL file, or however it is you're defining and registering your class).
I guess the developers of the distributed component figured that they didn't have to follow the rules because everyone else was going to follow them.
And, no, I don't know what component it was, or why they decided to copy the sample.
So here's a good rule of thumb. When you're designing a COM component, you should probably use UUIDGEN (or UuidCreate()) to generate unique (and separate) GUIDS for the Interface ID, Class ID, and Library ID and App ID.