I had a black one, with green eyes, living on my mess of a desk, last summer. He was about 1/2" long.
As he would walk over stuff, or climb the curtain, I'd make a sudden move, and he'd rear up, with his little front paws, spread wide, saying, "You want a piece of me."
After about a week, he was struggling to climb over pens, or up the sides of books, and would fall over...I'd put him back on his feet.
One day, he climbs up on my foot pillow, which sits on the desk, [It's a big desk] and just sat there, all evening, about 6" away from my feet.
The next evening, when I came home, he was curled up, under the computer screen.
It really made me kind of sad.