Luke Wroblewski's book on web form design starts by telling us to build things from the outside in. He does a great job of explaining the merits of user centric, task focused design by describing what it isn't.
Simon Willison (simonwillison.net) suggests I “hire a fort” for a week... all I've got is an office for one night and a simple quest: Build a Django app to power listofone.
Truthfully, Simon would probably classify this as more of a hack day than a /dev/fort, but hey I like punny plays on words. Especially, really geeky puns that only I get. So, fort-night it is.
Traditionally, when user hits Enter while using a form it is submitted to the server for processing. Rich Web 2.0 applications should throw this tradition, users no longer expect this behavior. Instead the context in which the user presses Enter should determine what the application should do.