The most eccentric karate sensei/dojo/style you encountered?

[Himokiri Karate]

Have you ever met people in karate that were just something else...

To give you a counterexample, Rick Hotton is a beacon of wisdom, maturity and quality in karate and a person who is sound of mind as well as being very artistic and very well read. 

Keep in mind, by something else, sometimes they can be really good or really bad. But mainly different like maybe they have good training but bizarre human beings or really nice people but not very good at being a sensei. Or folks with unconventional training that may either be bad or absolutely the most amazing thing ever.

[Nidan Melbourne]

Can't say that I have met anyone like that in my 20 odd years of training. But it does make me think about my early days. 

[Spartacus Maximus]

only a few known by reputation, and one noteworthy known personally as a private instructor. Cannot give his name, but its fine to talk about some of his eccentricities. 

[wildbourgman]

I like what I've seen from RIck Hotton and Steven Ubl. I wish shotokan would have had more folks like them when I was younger.

[KarateKen]

I've trained with some students that were scatterbrained but that is different than what you are asking. 

[Spartacus Maximus]

There was one Okinawan teacher who got rid of yakuza types who attempted to intimidate him thinking he was an easily scared old man. They would not so subtly remind everyone that the building where the dojo was and many other parts of the neighborhood was their turf, and therefore owed them something. They often showed up  acting arrogant, threatening and belligerent demanding recognition and « respect ». 
 

Instead of cowering in fear, the 9th dan 70 something sensei invited the yakuza in and showed them his personal makiwara, which was basically a piece of iron/steel sheet. After striking it a few dozen times with his hands and then with his toes(similar to sokusen kick in uechiryu), he asked if any of the yakuza characters wanted to have a go. One tried to look tough not to loose face, but visibly winced and very obviously could not continue beyond a couple of halfhearted punches. The sensei asked if anyone else wanted to try, but they all looked at each other, gave a sheepish bow and left. They never bothered him afterwards, even ignoring him if they saw him.