Since I gave up sugar in 2002, I have a protein shake for breakfast virtually every day (sometimes, if I'm daring, with a wasa cracker!)
Before I gave up sugar. I would have a Carnaton Instant Breakfast every day, so this question is sort of a non starter for me. It would be harder if I had to have something different for breakfast.
I do love breakfast foods - but I like them later in the day.
And I frequently have a bowl of lowcarb cereal as my late snack.