Here's an example from Frederick where the explicit opportunity cost appears large:
"While shopping for my first stereo, I spent an hour debating between a $1,000 Pioneer and a $700 Sony. Perhaps fearing that my indecision would cost him a sale, the salesman intervened with the comment "Well, think of it this way--would you rather have the Pioneer, or the Sony and $300 worth of CDs?"
Wow. The Sony--and by a large margin. Twenty new CDs were too great a sacrifice for the slightly more attractive Pioneer. Although I could subtract $700 from $1,000 and was capable--in principle--of recognizing that $300 could be used to buy $300 worth of CDs, I hadn't considered that until the salesman pointed it out."
Here's an example from Frederick where the opportunity cost is framed to sound small:
And here's a political example of making opportunity costs explicit, from the 1953 "Chance for Peace" speech given by President Dwight Eisenhower, who said:
"The cost of one modern heavy bomber is this: a modern brick school in more than 30 cities.…We pay for a single fighter with a half million bushels of wheat. We pay for a single destroyer with new homes that could have housed more than 8,000 people."