Fortified Oat Flakes
Stax
Anyone remember either of those?
Edit: Oops. I see Stax mentioned above. Those were really good
Maple Pecan Clusters from Trader Joe’s (Oat/pecan granola clusters with corn and multigrain flakes)
Grape Nuts 
Ugh - hated those. Only a little more chewy than gravel, and not much more flavorful.
Ha! My wife loves them, and I always refer to them as “Gravel Nuts.”
I love cereal in general, but these were so much better than anything else and anything since.
I currently eat Honey Nut Cheerios for breakfast, but when I was a kid I ate the usual stuff they eat, mainly Cocoa Pebbles/Krispies and other chocolatey cereals.
I see on this list 100 All Time Greatest Breakfast Cereals that #8 is one I don’t remember…Kellogg’s Concentrate ?
Interesting that there’s so many on that list and mentioned here that aren’t around anymore.
Thanks for all the great responses 
Cap’n Crunch. If the roof of your mouth isn’t hurting, you’re not eating enough.
Cinnamon Toast Crunch, straight out th’ box,
I used to love Frosted Flakes, but something about the flavor of the sugar grates on me as an adult.
Quaker Oat Squares
Peanut Butter Cap’n Crunch
Kellog’s Frosted Flakes (they’re grrrr-ate!); Captain Crunch; Life; Golden Grahams.
I like raisin bran, too - when I can eat it fast enough to finish it before it turns into nasty, soggy glop…
Gee, reading all of the responses, I feel that I was a deprived child (we ate hot cereal for breakfast).
My current favorites are
Peanut butter Cheerios
Special K with berries
Great Grains pecan
Life
Wheat Chex
Kroger chocolate oat rings (like cheerios, but chocolate and super for a quick snack if I don’t overindulge)
Most mornings, it’s still oatmeal though.
Mmm, oh yeah, baby. That’s the stuff. Thanks for the reminder.
Cheerios
Right now, Raisin Bran and Frosted Mini Wheats.
Cereals common in my youth included:
Cookie Crisp
Captain Crunch
Crunch Berries
Apple Jacks
Lucky Charms (I just wanted the marshmallows)
Actually when I was a lad in the store the toys offered in the cereals guided my purchase requests. Once I wound up with Sugar Smacks, bleah!!
No, but it’s wrong that because Zaphod Beeblebrox called him that ONE time, it stuck, and people treat that as his actual name.
I HATE YOU ALL.
Also, Wheat Chex.
Luck Charms came out when I was about eight, right in the target demographic, and I’ve loved them ever since.
A few years ago, Kellog’s came out with “Frosted Bran Flakes”, which were actually quite good, but I couldn’t help but think, “The Baby Boom Meets Middle Age”. They didn’t last.
Used to like Kix as a kid. But somewhere along the line they changed the taste and me no like…
I still get Cheerios once in a while though.