I have been called Lurch from time to time due to my propensity for saying "hmmm" when I am deep in thought on another planet, but since I have been told it comes out as "u-u-u-u-gh" I am really not too surprised, though it worries me that people really do not have that much imagination.
I have also been called Rodders by my aunt, a nickname of Rodney from only fools and horses for no other reason than I am very tall and quite lean. (And I am sure she thinks it is the height of intelligence from her because she assumes I do not know that she thinks I am stupid...but I am not going to correct her, she wouldn't understand my reasoning anyway and sometimes letting others think you do not know what is going on can be an advantage to observing the ants as they scurry about in their pointless little lives)
Can't think of any others but I am sure there are some said behind my back.
Ooh yeah...I sometimes get called Shaggy by reason of my flyaway hair and scraggly beard, and once for a completely different reason
If you put 2 pictures of us together though the reasoning for that one becomes immediately apparent.