Came across a blog this morning by Farhad Manjoo at Slate about the use of two spaces after a period: http://goo.gl/S6FqU
He goes on to explain the history of this practice and urges everyone to get a clue and stop using two spaces!
Farhad explains how many typographers react to double spaces:
Type professionals can get amusingly—if justifiably—overworked about spaces. "Forget about tolerating differences of opinion: typographically speaking, typing two spaces before the start of a new sentence is absolutely, unequivocally wrong," Ilene Strizver, who runs a typographic consulting firm The Type Studio, once wrote. "When I see two spaces I shake my head and I go, Aye yay yay," she told me. "I talk about 'type crimes' often, and in terms of what you can do wrong, this one deserves life imprisonment. It's a pure sign of amateur typography." "A space signals a pause," says David Jury, the author of About Face: Reviving The Rules of Typography. "If you get a really big pause—a big hole—in the middle of a line, the reader pauses. And you don't want people to pause all the time. You want the text to flow."
So please, tell your students, your friends, your neighbors, your manicurist, for cryin' out loud: STOP USING TWO SPACES!
I thank you, and I'm sure Farhad would thank you too.