I'm a student, and I do a lot of code on a small (12.5", 1366x768) laptop screen that I carry from class to class. Most programming environments are designed with the idea that someone has large screen size available, because most programmers do in fact have access to large screens. However, large screens are difficult to carry to class all day, and my previous laptop (15", 1920x1200) often got left in the dorm just because it was so friggin heavy.

I'm pretty much locked in to Visual Studio at this point; no program I've ever used is as productive for the kind of code I work with (after installing Whole Tomato's Visual Assist and Jared Par's VsVim, of course :) )

(I've seen other questions about small screens but they all pretty much go with "leave Visual Studio" -- which is hard given some of the kinds of development I've been doing....