I'm using PSPad as a code editor but I'm not sure whether ClearType is enabled. Although one may say that if I see no difference that I shouldn't make a point of it, but I'm just curious to know.
I'm using the Consolas font (which is said to be optimized for ClearType).
If I disable/enable ClearType on Windows, I do see difference everywhere on Windows (menus etc), except in the code editor. So either ClearType is not enabled within the code editor at all, or Consolas is always using ClearType. I do not know.
Hopefully this image clearifies it (is this drawn using ClearType?):