An App Security Checklist from Google
Security should be taken seriously. These are guidelines that apply to web development also.
Hiawatha: The No BS Web Server.
Designed around security and performance, this web server is probably the best that's available for both high-end and low-end servers.
Prevent Form Data Loss with jQuery
Dummy proof your app and ensure your data is saved, always!
Private File Share
A totally new, awesome anonymous file-hosting service.