A film about a typeface to be released in 2007: http://helveticafilm.com/
Microsoft uses a typeface called "Arial" that I discovered only recently is NOT the same as the "Helvetica" font found on Macs. The differences are subtle to my untrained eye, but those with a background in typography don't take the discrepencies lightly.
On the battle between Helvetica and Arial
Helvetica vs. Arial: http://www.engagestudio.com/helvetica/
How to spot Arial: http://www.ms-studio.com/articlesarialsid.html
Arial or Helvetica?: http://www.iliveonyourvisits.com/helvetica/
Wikipedia's article on Helvetica
The real evil: Comic Sans
The Arial's existence is tolerated by those in-the-know. Comic sans is hated. That is is a shame, because its designer, Vincent Connare, also designed one of my favorite fonts: Trebuchet. Read what Vincent says about Comic Sans.
Trivia: I first knew Vincent as a teammate on an ice hockey team. I remember him as a skilled player and an excellent sportsman. Only later did I discover his contributions to Microsoft's typography.
Wikipedia's article on Comic Sans: http://en.wikipedia.org/wiki/Comic_Sans