Taboo was my first rat.  I was introduced to rat ownership at age16 after reading an article in a magazine about how they were such great pets.  Taboo (or 'Boo') was true to the article's description and was a wonderful pet.  Sadly, I lost him to a tumor when he was just over 2 years old. 

Boo was a friendly, somewhat shy rat.  I am now convinced that his shyness was a result of him being kept alone without cagemates.  He still lived a long life and was always happy to see me, but I think he would have been much more confident like Rimsky and Korsakoff (which were kept as a pair) if he had had a cagemate.  I am now a strong supporter of rats being kept in groups of two or more.