Mutts are lovable, adorable, and intelligent dogs that usually don't have as many health problems than purebreds. Like @LisaLisa said, they're usually found abandoned but, no matter what they've been through, they'll always bring out the best side of life!
Rotties have a special place in my heart- I've always had Rott/Lab mixes and get the best of both worlds. They get a bad rep, like Pits, for being dangerously violent dogs. It couldn't be further from the truth, they're lovable and loyal.
Labs- they have it all- they're playful, fun, sweet, up for anything and full of energy. They're one of the most popular breeds but, a word of warning, if you are going to adopt an adorable Lab pup- make sure you know what you're getting into!
A wolf and a dog, usually Akita or Husky. This is the only dog that could beat the Husky in beauty. When it looks at you, you feel as if it's looking through you. It is HUGE and requires a great deal of care, make sure you have a big yard with an incredibly high fence (these guys have been known to be jumpers).
Like @LisaLisa said, this is an apartment dog, a mix between a Pug and a Beagle, it's adorable! I looked into getting one of these, taking into consideration that I live in a small place. However, you should be warned that this is an extremely active dog and needs an energy level to match it.
SO cute, I think of these as the friendlier Pit Bulls, in a PR sense- we'll get into that later. Boxers remind me of a Pit's body and they will act like a puppy for a long time after they've already outgrown their "puppy" age. They will always think they can hop in your lap.
Pits get a bad rep and it's really more to do with their owners than them. Well, that and they aren't the biggest fans of other dogs. Pits are incredibly loyal, LOVE people and are protective. They reign the shelter system because people don't do enough research before getting one and think that they're the cool things to have. Dogs are not accessories, that's why I don't have any small dogs on my list ;P nor will you find me putting my future dog in a stroller or dressing it up if it's not Halloween. And really, I would just do that to entertain myself...
Smart, gorgeous, protective and fun- they make the perfect little helpers to anyone, usually police. Bred for their intelligence and ability/willingness to be trained, they are third in intelligence amongst dog breeds (behind Border Collies and Poodles). However, they are known for aggression and are responsible for the most random bitings in the US and are likely to attack smaller dogs.