Serious Sans is a more professional take on Microsoft's much-maligned Comic Sans typeface. The typeface is a project by four students at the Royal College of Art in London. From The Moment blog:
Struggling to understand what could possibly be good about Comic Sans, Valerio -- together with partners Hugo Timm, Filip Tydén and Erwan Lhussier -- found that the doggedly goofy font's irregular forms made it one of the easiest typefaces for dyslexics to read. The designers also liked how it undermined the authority -- and changed the meaning -- of texts set in it.