Fortunately cereal is constantly on sale, so my cereal consumption is a steadily revolving door of something that easily qualifies as my "favorite" for as long as the box lasts.

Cap'n Crunch / Crunch Berries
Lucky Charms
Coco Puffs
Cinnamon Toast Crunch
Golden Grahams
Froot Loops
Trix
Smacks/Golden Crips
Frosted Flakes
Cheerios (including fruit and honey flavors)
etc

I'm pretty much always stocked with at least three of these at any given time.