After reading this question I installed Consolas. The trouble is, now the text seems too small. I have to adjust it to size 12 to use it comfortably. Anyone else experience this when switching to Consolas (or any other font)? Do my eyes just have to adjust to this new font or is it a sign that my eyesight is deteriorating?
My resolution is 1280x1024
I use Consolas, 11pt on my 1440x900 laptop (Windows XP). I've been using 10pt for some time but I found myself having eye strain so I've set 11pt for all the development tools, editors and shells I'm using.
I would, however, be much hapier if 11pt Consolas would be a little smaller. I don't like that big difference between Consolas 10pt and 11pt.
I use Consolas 10pt on Windows, and have found it to be extremely legible no matter what my resolution -- or more specifically, the monitor's DPI -- was. This is on dual 19" 1280x1024 monitors, my home 19" 1440x900, a 15" laptop at 1024x768 and a 15.4" laptop at 1440x900 (which was the only one where I even considered adjusting the font size).
Now, where it gets tricky is in a Mac world. (Yes, I did a Bad Bad Thing and copied the font onto my Mac for XCode.) In the Mac world, I found 10pt to be completely illegible no matter what monitor I was hooked up to. For Mac, I adjusted myself up to (I think) 12 or 14pt. However, on-screen, that wound up being about the same size as 10pt in Windows for me, so it was the same net all around.
I used to love ProFont. Until I discovered Consolas.
I use Consolas at 12 point too; I think I used to be 10 point Courier New.
The resolution of your screen is irrelevant without the size of the monitor. You'll need a bigger font size on a laptop than on a 24" monitor even if the resolutions are the same
These days I have been using Source Code Pro (open source font from Adobe) at 14pt. I used to use fonts at a lower font size but I don't want to strain my eyes, and I find 14 to be very readable and doesn't strain my eyes at all.
I can generally fit 44 lines of code on my terminal with this font/size. I think that is plenty, plus straining your eyes less is priceless.
I use consolas 10 point on a 1280x1024 screen & 11 point on 1600x1200 screens. It is remarkably clear even at small sizes.
I have WinMerge set to use it at 8 points, it's still readable and I can compare code side-by-side without scrolling left and right (although, I wouldn't want to use it for coding at this size).
Consolas 10pt
I also invert my IDE colors to run light yellow type on a dark blue background. I think it was an old Borland standard configuration that I have since adopted.
Anyway -- I find it helps a lot on eyestrain (you're not staring into white light all day) and as such it helps with text clarity.