I saw this on Apartment Therapy last week and have been meaning to post it for others to see.. It is a brief 6 minute file about Hoefler & Frere-Jones type foundry. This company has created some of the best known and successful fonts.
This is a little behind the scenes about why they create fonts and some of the process on how it starts. Unfortunately there is a legal battle between the two now so what will happen with the foundry remains to be seen.
If you are a type nerd though it is worth your time.