(only open to people who are allowed to work in the US) (There is the International Associates program for those not eligible for the CAs)
The GDC CA program is one of the few ways you can attend GDC for free (minus hotel/food/transportation costs).
If selected you get to:
1) Free Full Access ticket
2) Free GDC Vault access
3) a Lunch credit card to buy lunch on the premises
4) More importantly, you'll be volunteering and hanging out with a very aggressively intimate networking situation and people you'll be in contact with throughout the year.
I really encourage people to apply if you want to finally go to GDC, or see GDC in a different light.
I've been doing it for 7 years, so if you need help with the application, feel free to ask me questions.
Deadline is December 22nd