Woman finds rat on the street. Now she can't live without him.
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I got a solid B in what was a pretty tough course because he was so smart. He was a Hooded Rat, looked just like this:
.. The prof in rat lab said I could take her home after i worked on mazes with her. She had the run of the house and would sleep on my dtrs pillow at night. She potty trained herself to go in hubbys sock drawer 
She would run to the door and greet people..she would climb on my shoulder when I did the dishes. She lived about 18 months. She was a great little friend.
I kept my lab rat from Experimental Psych. He was very smart and of course I got attached. My professor warned me that I couldn't bring him back - like I'd ever consider it since I knew what would happen to him. Mine was always a little nervous after living in the lab, wasn't all that fond of leaving his cage when I cleaned it. That is very cool that yours became so tame and playful. 
I'd previously had a pet mouse like that (also black and white) so I thought nothing of keeping my rat. My mouse's name was Franklin D Roosevelt - Frank for short. And when I went to summer camp, my grandmother "mouse sat" for me - she was quite fond of Frank.
