I had the huge privilege of participating in a seminar led by Jim Baker Sensei back in December. He is a fabulous hoot! And, he can do all that wierd, cool stuff where he barely moves at all and grown men go flying across the mat (very O-Sensei-looking). We had visitors from other dojos including instructors from other dojos.
At one point, he explained a technique and got us to practicing and then commented that if we needed some help, there were plenty of penguins (instructor types in hakamas) walking around we could ask. This was my introduction to AaaRk Sensei.