Concept: A System that allows web surfers to configure their own Keyboard Shortcuts for web applications.
Probably a firefox extension or chrome plugin, but also a web directory where visitors can install greasemonkey scripts that will add keyboard shortcut functionality to various apps. The full add-on will be promoted to be able to notify you of configuration change possibilities and specific website productivity tips, all based on the current URL in view. Users will be able to change/add/remove keyboard shortcuts for every URL.
Challenges:
– compatibility
– change monitoring
– conflict resolution