Is there a half-decent substitute for coffee on the market?

I’d like to try life without coffee because the GI effects are troubling me. Decaf won’t do; it’s not just the caffeine but the properties of coffee per se.

All I want is two cups of a warm and preferably mildly stimulating beverage in the morning, one that won’t make me sleepy (as a nice herb tea will do) or load on the sugar (so no hot chocolate).

My granny used to drink Postum, but it’s not on the market any more. Not that I’m sure I’m ready to become granny, but I might have tried it.

Can you recommend a hot beverage that satisfies the coffee urge without the side effects?