Fruity Pebbles.

I use to watch the Flintstones a lot when I was younger and the commercials just made me want them. I still eat them(albeit, the store brand)...but still. The only problem with them is that once your bowl is nearly empty, it's hard to scoop up the remaining pebbles.

I also like Cherios and Cracklin Oat Bran...as well as some adult cereals like Basic 4 and Honey Bunches of Oats.