Google Code University publishes many online materials, where you can learn about programming and application security. You can find topics in the area of programming languages, web programming, web security, databases, Linux, etc.
They have also released many tools in this area, the latest being web application named Gruyere. This is similar to OWASP WebGoat or Mutillidae.
The tool shows how web application vulnerabilities can be exploited and how to defend against these attacks. Some of the vulnerabilities that you will be exposed to include Cross-site scripting (XSS), Cross-Site Request Forgery (XSRF), Cookie Manipulation, Cross Site Script Inclusion (XSSI), Path Traversal, Denial of Service, Configuration Vulnerabilities, and specific vulnerabilities affecting AJAX.
It is a great tool to learn application security.
Links:
Google Code University : http://code.google.com/edu/
Gruyere web application : http://google-gruyere.appspot.com/#0__hackers