Effects
Another good NW idea that I don't have time to implement: I was thinking about animations (and how NW really doesn't do them well, or at all), and it occurred to me that each component should be allowed to attach "behaviour" objects to itself.
In a similar fashion to what I'm mulling over doing with keystroke dispatching, I think that running a "thread" that calls the behaviour of each "activated" component might be a good way to effect complex animations with a minimum of fuss and a maximum amount of extensibility. This way, if you don't need an effect (or behaviour), you don't have to include it.