Seaside statefulness
In this recent post, Loren Segal begins a nice long post with:
The interesting part is that playing with Seaside is completely unlike learning Smalltalk (unless you’ve never seen a language with lambdas). It’s a complete mind-blowing experience on its own level; a revolutionary way to look at web application development, not "let’s do what Ruby on Rails does.. in Smalltalk!".
Read the rest of the post... he's got a good simple example of what continuations are all about.