I recently purchased a Lenovo Yoga 2 Pro, which sports a high-dpi 13" screen with a resolution of 3200×1800, running under Win8.1.
The issue I sometimes face is that some applications will not scale properly and will look tiny on screen, making them almost unusable.
I'm aware of the scaling options for Win8 and of the magnifier tool (that you can call using the and + or - keys), but it will magnify parts of the screen only and its use is cumbersome since it is indiscriminate.
Ideally, what I would need is a utility that can automatically resize the windows of a given application or at least a selected window.
I'm sure this is an issue that will become more common as high-dpi screens become more mainstream for Windows machines.