Granted, in Bluebirds we called it a Buddy Burner and made the fuel canister out of a tuna can, cardboard and melted paraffin (as described at the link). The Sterno didn't burn as hot as I recalled the paraffin burner doing, but that is just as well considering I was cooking on the hearth of our fireplace - I was still able to boil water for tea, cocoa and soup on it.
There really is something psychological about hot food, I've decided. Obviously a person can survive on foods that aren't heated, and I've even done it inadvertently at times, but I felt infinitely better Friday afternoon with a cup of hot tea in hand.
The paraffin-burner version gets hot enough to cook eggs or french-toast, as I recall.