What's the best way to react when a camera is pointing at you so that you look real/not like an idiot in the photograph?

To find some answers, go here. Good suggestions include:

• Clench your butt cheeks.
• Try not to look at the camera lens, but the eyes of the person behind the camera.
• Hold your shoulders back, stick your chin out as far as you can, turn your face so it's at a 3/4 angle, tilt your chin down a little - hence, the "MySpace pose" or taking photos from above.
• In a group portrait (especially an informal one) people have a tendency to lean in toward the person in the center. Don't do that.
• Think of the most hilarious and/or satisfying thing you can imagine while the picture is being taken.
• Imagine that the camera is a child you love and smile warmly and sharingly at that child, like you're whispering "You're so cute!"
• Try looking away from the camera at something else, then imagine that an old friend has just called out your name from the general direction of the camera.
• If you are standing, turn slightly and rest your weight on one foot. It may feel goofy, but you will look better.
• If you are sitting, angle to one side or the other.
• Lean slightly towards the camera. Leaning slightly towards the camera adds interest, dimension, and a natural look to a photo. Think of having a long neck like a gazelle, and tilt your chin down just a bit to avoid the appearance of a double chin and also to prevent the camera from getting a view right up your nostrils.

I came across that when I was retracing Jenny Diski's trodden path. She mentioned MetaFilter.com in her "Short Cuts" piece in the LRB and that was the first question I followed on Ask MetaFilter.