I think most people prefer to see rats as villains, and there is a very good reason for it. In real life, they are absolutely a nuisance. They breed faster than we can control them, and they spread diseases and leave droppings everywhere. They are about as detestable as it gets.
I think this is why they are often portrayed as the bad guys in stories and such. I really do not mind this! They are big and scary things. Rats are also very glutenous and can get big and fat! I like to see them portrayed as such.
In the movie Heidi's Song, rats were displayed as purely detestable creatures who loved filth and wanting nothing but to be nasty and bad. There was even a great song about it which I just MUST link for your viewing pleasure: http://www.youtube.com/watch?v=Ll3bBOobKd4
Interestingly enough, Pixar made a movie called Ratatouille that actually showed a sweeter side of rats while STILL showing the nasty ways they live among us. I totally approved of this as well.
My first novel (unpublished until I can get it up to par with my current stuff) was all about the rats, but I showed both sides to them. I see them as the bad guy, but I also believe they can be a strong, powerful force of good if they choose that kind of life. I think that all species of rodent can be shown with both sides in some ways. Imagine if a mouse gained a rat as a companion. What a great ally that would be in whatever trials he would face! But still, you have to admit, it's great to see them staring down at you with those evil eyes of red, and you just know that his intentions will be less than civilized.
Feel free to comment on this blog, or you can email me at firstname.lastname@example.org! Have a ratty day!