I did not recommend ferrets, because I don't think they would be a good fit for your house. I had one when I was younger and he was a freakin amazing pet! However, I got pretty lucky with him because he had very little smell and he was very sweet. A lot of ferret tend to stink to high heaven and they can be active and nippy. They are not really a pet you cuddle with, they are expensive (Think about $500 or so to get started with cage, supplies, ferret itself, etc. Ferrets also need regular vet care and vaccinations, as they are quite susceptible to distemper. As ferrets get olde,r it is actually recommended that they see a vet every 6 months because they tend to get really bad adrenal and pancreatic disease. They are also a high maintenance pet that require regular baths, nail clipping, etc. Training them for a litter box can be done, but it is not as innate as training a cat and can take some time.
They are awesome pets and I may get a couple down the road, but definitely not a good pet for young children and they can be rather mischevious, which can be an issue for people that don't really care for animals.
I agree with the others. I had to wait until I moved out and was relatively stable to get a dog (thanks to vet school I can actually afford the care for her, otherwise I would have had to wait until I was done with school for good!) I did have a crested gecko in college though, and fish while I was home. Both were fun pets and the fish tank can be a really nice hobby (albeit expensive). The crested gecko is a nice pet, but mine is not cuddly. She tolerates holding fairly well though.
If you really want companionship (both people and animals) go volunteer at a shelter. You will become an invaluable member of the shelter, you will get to meet tons of cats and dogs, and you will really make a differene in their lives. There's volunteer work for just about everyone, from walking and cleaning, to helping with the feeding, vet care, and just playing/interacting with the animals. My experience volunteering with a shelter was what gave me the last push I needed to apply to vet schools, and I made lasting friendships with people that I still talk to!