This hint will add highlighter styles to the styles menu of the OS X apps TextEdit (which is part of OS X) or Bean (a slightly better freeware app):
Create highlighter pen effects in TextEdit
Published by Michael Prewitt
Michael Prewitt is a creative director who has in graphic design since 1992. While his primary work is design and layout, he also has skills in writing and editing, web developing, front-end and macro-type programming, photography, photo retouching and compositing, and branding. View more posts