Take a look at "Emotional Design" by Don Norman (http://www.amazon.com/o/asin/0465051359/pchristensen-20 http://www.amazon.com/o/asin/0465051359/pchristensen-20

Take a look at "Emotional Design" by Don Norman (http://www.amazon.com/o/asin/0465051359/pchristensen-20 http://www.amazon.com/o/asin/0465051359/pchristensen-20 ) The thesis is that if you present people with two [websites, machines, etc] that function identically but one is beautiful, people will be measurably better at using the pretty one, and they'll enjoy the experience more too.