Oh yeah, I had a hamster once. They just do that kind of thing.

Hate to say it, but that same hamster was easily the worst pet I've ever had. Had to wear work gloves when handling it because of how often it tried to bite. It bit my brother so badly that blood dripped on the floor. I also used to keep it by my bedside to watch it and it thanked me by putting its rear up against the cage wall followed by it spraying piss all over my bed. I was tempted to return the favor.

That's one pet where if it didn't make it to the rainbow bridge, I wouldn't be too upset...