I enjoyed this poster today (for the Telegraph newspaper) with a boot labelled "A Nokia, 1979".

You might not realize this, but until the early 1980's Nokia was largely an industrial company in the rubber production business.  A small investment in switching equipment, and then early mobiles led to involvement in the GSM standards, and ultimately to the company they are today with a $50 billion turnover, largely from telecomms. 

Quite a nice accident to have, and an illustration that you can never tell which products are going to be the killers.