When I contacted the founders of the Lebowski Fest for advice and information on organizing such an event, I received the following email response...
We have to ask that you do not use the name "Lebowski Fest" for your event. We've worked hard to establish our name and our event and don't want anyone to be confused as to who is doing what.
You can call it anything else, just not Lebowski Fest. That's our name, Dude.
That was it. The Dude abides, so we'll call our event something else. Any ideas? I have a few...
A fun event by any name is still a fun event! Check back here for details.