I find it particularly interesting that most of the businesses covered here run at a profit margin of about 10%. I guess it is safe to say that many of us belie

I find it particularly interesting that most of the businesses covered here run at a profit margin of about 10%. I guess it is safe to say that many of us believe that the margins of successful software/Internet businesses can be much higher than that. At the same time, when seeing these examples, I wonder how realistic this is for the average profitable startup.