Matt Wiebe

The HTML editor has not received a lot of love. The type is too small, especially when you see it in the new distraction-free writing mode. This plugin uses the lovely <a href="http://mplus-fonts.sourceforge.jp/mplus-outline-fonts/index-en.html" rel="nofollow ugc">M+ 2m font</a> (the font I use for coding every day) for more beautiful writing.
M+ also has extensive international support. <a href="http://mplus-fonts.sourceforge.jp/mplus-outline-fonts/index-en.html#features" rel="nofollow ugc">From its site</a>:
<blockquote>
All fonts were completed with Basic Latin, Latin-1 Supplement, Latin Extended-A, and IPA Extensions. And most of Greek, Cyrillic, Vietnamese, and extended glyphs and symbols were prepared too. So the fonts are in conformity with ISO-8859-1, 2, 3, 4, 5, 7, 9, 10, 13, 14, 15, 16, Windows-1252, T1, and VISCII encoding.
</blockquote>

HTML Editor Type

Uses the lovely M+ 2m font in the HTML post editor for more beautiful typing.

jayrobinson

Designates a monospaced font in the HTML editor. Maybe more in the future…

Jay’s WordPress Admin Theme

Designates a monospaced font in the HTML editor. Maybe more in the future...

HTML Editor Type vs Jay’s WordPress Admin Theme