Great question — answering as the UphillTech team:
If you try regular oats and like them, then you might try flaked/rolled barley, if you can find it. If you have refrigeration at work (or just bring in one-day's worth each morning), you could also add wheat germ (I can't imagine having a bowl-ful of it, but adding some to your oats would change them up.) Wheetabix or shredded wheat can also be prepared with boiling water for a hot cereal. Late recall - "Grape Nuts®" is another one that can be done hot, even if it normally isn't.
Full answer by Ecnerwal: https://cooking.stackexchange.com/a/58007 (CC BY-SA 3.0).
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