Google Summer of Code is a global program that offers students stipends to write code for open source projects. Participants work remotely from home, while getting guidance from an assigned mentor and collaborating within their projects community. The application deadline for Google Summer of Code this year is April 6 and the program dates are May 21 to August 20. The stipend for the program is $5,000 (USD).
The organizations that will participate in Google Summer of Code this year will be announced on March 16, but the best way to prepare to apply is to become a contributor of the project that interests you early on. There are people in many organizations who are happy to help newcomers fix their first bug. Take a look at this listing of mentors in different organizations, who can help you along the way.
Please consider applying for Google Summer of Code, encourage someone else to apply, or help spread the word by sending a prepared e-mail to university Computer Science departments and technical women groups.
In particular, there is an effort underway to send the information about Google Summer of Code to as many women in Computer Science groups at universities as possible. If you can find contact information for one university listed on the wiki page and/or a university you went to, sends them the e-mail, and update the wiki page, it would be a huge help!