I never eat breakfast until I get to work (long story), so it's hard for me to eat a meal that has to be prepared. My favorite thing lately is to bring a bag of cereal and a juice-box sized Soy Dream Original (I believe they sell 3-packs of them). Pop a few cereal pieces in my mouth and wash it down with the soy milk - just like having a bowl of cereal!
I will also bring pieces of Heathers' breads or an english muffin to toast in the toaster.