I love brown dogs. Especially a rich, deep, chocolatey brown (like Ripley). I've always had a thing for brown dogs. If a dog/breed comes in different colours, and one of those colours is a shade of brown, then I'll always opt for the brown as my preference (whether or not it's actually called brown -- could be liver or red or chocolate depending on the breed). For example, I like: liver Dalmatians, liver Flat-Coats, red Dobermans, red Border Collies, etc.
Merles (blue and red) are another favourite of mine, but I'm kinda picky on the pattern. And I like orange and red dogs too (like Tollers, Pharaoh Hounds and Ibizans). Sable is another favourite of mine.
And I like my dogs to have markings. There are a few solid breeds that I like, but mostly I tend to prefer a dog with markings (be it rust points, spots, white areas, a mask, etc.).
As for my favourite colours in my breeds, I'll always have a major preference for red Dobermans over black. And the darker the coat, the better. With Tollers, I prefer medium-minimal white and a rich, dark red coat, but I'm not too picky with Tollers as long as they're not very heavily marked.