My wife was watching the Home & Garden channel this afternoon (she's addicted to it), when a show came on called "Pet Pads" that featured Jim and Linda Sautner of Alberta, Canada, who keep a 1650lb pet buffalo named Bailey in their home. Remembering that I had recently posted about a woman with a pet moose, she called me in to see the show. It was pretty interesting. The buffalo had been trained to wipe its feet on a mat, as well as to turn on the light (the light was touch sensitive, so the buffalo only had to touch it with its snout). Of course, the buffalo didn't live in their home 24 hours a day. There was a pen for it out in the barn. I figure that since I saw the pet buffalo on TV, it must be a true story. (Kidding, but there are plenty of articles online about the Sautners and their oversized pet, so I'm sure it's real.)
Most buffalo can be quite aggressive, but Bailey was raised by the Sautners since he was a calf and has always been very tame. Also, the Sautners operate a buffalo ranch, so they know how to handle the creatures. I don't think keeping a pet buffalo would be a good idea for most people.