Hello everybody! I'm new here and saw this thread and it's right up my alley!
I currently own 3 snakes along with a host of other exotics. My favorite snakes are boa constrictors.
One...they won't get bigger than the very rare 10 feet. Usually stay between 6 and 8 max.
Second, they tend to be less skitish than pythons. Especially the big ones like Burmese and Retics.
Third, they won't take up half your living room, though a good 75 gallon tank will be needed at least.
Fourth, this is an animal that eats BIG rats, and later on probably rabbits.
I have to respectfully disagree with a couple things posted here though. (Sorry.

)
One, I would not suggest a heat rock. Snakes are very prone to thermal burns, and heat rocks are usually the culprit.
Second, I ONLY feed prekilled animals to my snakes for a number of reasons.
First, they do eat it. Most snakes kept in captivity will eat pre killed. They scent the rats with their tongue. Only pit-vipers detect the heat. Mine will even eat rats straight out of the refrigerator! Feeding live will almost always lead to a beautiful snake with battlescars. Rats have REALLY BIG teeth and when they get your snake (and they will) watch out!
I love the boas because they are large, but not HUGE. Beautiful and mostly calm. I suggest buying a good boa book and learning as much as you can about them, though. PM for suggestions!
(I tried to post some pics, but got rejected as I don't have enough posts.

) Go here to see my boa pics...
Meh. Can't do that either. I guess you'll just have to wait or PM me so I can give you the site.