I have several of them...

Sleet has a set path around the house that she absolutely must walk. If there is anything in her way, she can not, will not go around it. She stands there and whines until someone moves the obstacle--which can be very small.

Goldie absolutely will not leave the yard on a leash. If I am taking her for a walk, I have to drive her somewhere to start. She's also never been in any part of our house except the bedroom. She goes straight there when she comes inside and doesn't move.

Pingo has to run on the left side of everything, especially when she's in harness. Put Pingo on the left side of the team and she's amazing, put her on the right and all h@@l breaks loose.

I'm sure there's more, but those are th first ones I thought of...