I remember the first time I saw this, I thought it was such a good idea. BonjoviBabe and a few others show their customers the size of a standard piece of cake with wooden blocks painted to look like cake. Although 1x2x4 sounds tiny, it looks bigger---and is a decent-sized piece of cake-- when it's on a plate.

http://www.cakecentral.com/modules.php?name=gallery&file=displayimage&pid=88648

This probably wouldn't work as well for birthday and other occasion cakes, because there's not always a sit-down, face-to-face consultation when ordering. The diagram showing how to cut the cake taped to the top of the box sounds like a great alternative.

Although I'm not overweight now, I have been pretty obese at other times in my life. I have mixed feelings about whether we should support the upsized norms of how large a "piece of cake" is. Certainly, if someone wants more than one piece (or two, or three), then s/he should have it. But shouldn't we be aware that we're eating two pieces or three pieces, rather than thinking we're just eating one piece?

Our ideas about how much food we should be eating have become so distorted in our US culture. Again, I'm not trying to criticize-- I don't even know that it's the consumers' fault for these distortions. I guess I'm just not sure as a baker, I want to support those perceptions.

To me, it's far better to eat regular-sized portions of all foods and enjoy an incredibly luscious, regular-sized piece of cake than to deny myself cake and wonder why I can't seem to lose weight. [Apologies---There's nothing worse than a reformed sinner, is there? ]

Yes, I show my wedding customers blocks of wood cut into the size of standard servings. I show the party size as a dessert size, and on 2 occasions my couples who had decided on party sizes changed them to wedding slices because they could see, even as dessert, it was enough cake!

When I'm dealing with Dutch couples or families, I worry even less - they cut tiny pieces of cake! I have a few times made Wilton novelty pans for class occasions (Xmas, summer picnic etc), and every time the teacher has served up to 30 kids with that cake, and had leftovers! Now, I can easily get 18 decent sized pieces out of most of the novelty pans and will advise customers that they will serve up to 24 at a push (after all, I make that many cupcakes from the same amount of batter!), but 30+ servings is really beyond expectations lol!