Beautiful and Free Unicode Typefaces, for editor and printer (including a comparison of Latin Modern and Computer Modern Unicode)
For my academic papers, I often need a typeface with a wide range of characters and diacritic combinations. Basic diacritics are supported by a wide range of fonts, but more specialised diacritics and particularly combinations of diacritics only work well in a handful of typefaces. I write my papers in TeX, which has two components: the typeface used to set the paper in (La)TeX and the typeface/font used inside Emacs, where I write the papers.