How useful is an iPad to college student? I like the iPad, but do have a budget constraint. I just got the 2011 MacBook Air, which is also very light and portable. But I am not overlooking the iPad, what are your thoughts? I am also considering the iPhone 4S, and noise cancelling Bose headphone($299). If I get them all, it would be too much, it's not even Christmas or my bday.