JavaScript Madness: Keyboard Events (2011-01-19) By Jan Wolter. @ Source unixpapa.com
Google javascript library Closure Library. It's used by many of Google's services (e.g. gmail, maps, docs, sites, books, reader, blogger, picasa) Heavy weight. It even supports drag'n'drop. At http://code.google.com/closure/library/.
Google OpenSocial API: http://code.google.com/apis/opensocial/. A API for building social networking sites, so that all social networking sites can have one unified API.
Google Web Toolkit. You use Java to create a GUI app, then the kit will compile it into HTML and Javascript so it can be deployed on the web. Seems that Gmail and GoogleMap is written this way.