Well someone mentioned using banana milk, which is a good idea. As is using chocolate milk for say a chocolate cereal, if you're really feeling chocolatey that day.
However some may also find it wise, extra tasty or convenient to use orange juice over milk when eating a fruity cereal.
Example: Fruity pebbles with tropicana orange juice. This is one of my favorites. Although I try to avoid the cereal isle these days...