I think most cats I see are mixed-breed domestic shorthair or longhair, but I have some guesses as to the background of my cats and others I know. Here are some pics as examples of colors or possible breeds:

Bailey is a domestic shorthair - we think his father was part Siamese, actually - he was a big guy who fathered many kitties in our old apt complex, which is where we adopted him from - they found 3 kittens in the shed, and our Bailey was the only male. He's a gorgeous brown tabby with white, but we don't know much about his background:



As for Leila, well, she is so tiny, yet limber and fast - she's also kind of long. She's very playful and acrobatic too. She's also tabby - she's what they call a calico tabby, b/c she has that calico pattern mixed with the brown tabby pattern. We think she's part oriental of some sort, b/c of her face and some of her behavior.
This picture really shows her markings well:



Leo is a good example of an "orangie" - he's an orange tabby. We're not sure of his breed background - it's mixed - the people at the shelter think he's part Persian b/c of his laid-back nice attitude, and I also think he could be part British Shorthair b/c of his larger, rounded head and his swirly tabby markings.



Claudia is a Snowshoe (mix), which is part Siamese, part domestic shorthair bi-color, I think - we don't know if she's full snowshoe or not, b/c she was from the same shelter that we adopted Leo from, but she certainly has the personality of a snowshoe, and she has the correct markings (and the blue eyes) also. Someone else told me she looked like she could be part ragdoll. Her hair is kind of long, even though she was short-haired last summer. She is also kind of short-legged, but solidly built.



Any breed guesses would be appreciated.