Hackers are more likely to have cats than dogs (in fact, it is widely grokked that cats have the hacker nature). Many drive incredibly decrepit heaps and forget to wash them; richer ones drive spiffy Porsches and RX-7s and then forget to have them washed. Almost all hackers have terribly bad handwriting, and often fall into the habit of block-printing everything like junior draftsmen.
Alan Turing is an especially famous example of a hacker with poor handwriting. At times he would make mistakes in his own calculations simply because he had misread his own figures and letters.