I've always had a soft spot for black rat snakes. I love finding them, and I've loved keeping them in the past, though I don't keep any currently. The first snake I ever held was a black rat snake, when I was about three. It fell out of a tree onto my dad while he was mowing or something like that, and he brought it in the house and let me hold it. I think that was the first thing that ever really got me into snakes. Their temperments can be a little unpredictable (I had one start chewing on my knee while it was watching TV with me, I had another that I pulled off the road bite me in the face while it was just hanging out in my lap a few seconds earlier), but I have had some that were very, very docile. They're a cool snake, I like the ones that have a lot of red in them, or the ones we get from Missouri that are just jet-black all the way down. Anyway, good luck!
Kevin