I treated myself to business class for my one-way JFK-NRT ticket earlier this year. I flew back and forth between NY and Tokyo last year, always in economy and with a layover somewhere, so the direct in business was nice. I bought it with miles (one-way flights on the "mainstream" airlines are not worth it otherwise), it ended up costing me just under $6.
I got upgraded to business on a ZRH-JFK flight four years back when I was still a college student. Getting on the plane, putting my coat on a hanger in the closet, sipping my champagne and looking out my three windows felt very opulent at the time.
Pretty much any business trip with my old company. We had a 25/25/75 food budget, and there were some days when we would exceed that for all three meals. 30 dollar breakfast, 50 dollar lunch, and 100 dollar dinner. Not outrageously extravagant, but I wouldn't be spending that kind of money if it were my own.