As we all know, the portions at restaurants are way too big, at least they are if you're trying to maintain a 2000 calorie a day intake. So as a way to deal with the big portions, my wife and I started splitting meals. This works out great! Half a meal is generally about the right portion and we're spending quite a bit less as a result.
When we can't agree on something, I've taken to telling the waiter to just box up half the meal before it even comes out. Then I have dinner or lunch for the next day.
Just a suggestion for those of you that eat out a lot.