I keep trying others and always end up going back to 6x13. It's the perfect font when working on a notebook.
At work I have a larger display that sits farther away, and am running windows. Consolas is easier on the eyes there with two Emacs buffers side-by-side (at "108" Emacs font height).
I came across the 5x13 font (https://github.com/chneukirchen/5x13) and wanted to try it on my netbook. For some reason spaces come out as hatched boxes for me. The font itself looks promising but needs many changes (some of which I've figured enough out to make; but I don't know what to do with the space).
There really is no other choice.
http://mirtchovski.com/p9/fonts/6x13.png