if there was a requirement that the user could quit the browser and come back a day later and get the results, then that would be more in the vein of continuations?

Using processes, what if the user moves two pages back, and resubmits a value? Your process and user input are in two different … places.

e.g. the simple example of two pages asking for a number each, and a third one displaying the sum will not work. Entering 1 on the first, and moving to the second page one cannot go back to the first page to correct the number to 3, because the process expects second number, not the first.

You would need to have some sort of automagic undo mechanism to get this to work with processes.

Too bad, this would be an elegant solution.

From Wikipedia, on US patent law:
Thus, merely thinking about an invention, or drawing a diagram, is not an infringement. Research for “purely philosophical” inquiry is not an infringement, but research directed to commercial purposes is – unless the research is directed toward obtaining approval of the Food and Drug Administration for introduction of a generic version of a patented drug.

So open source platforms, or little experiments like this are fine.

http://www.defmacro.org/

I remember Paul initiating the Arc Challenge and throwing it open. I thought it would be great to see Erlang/ErlyWeb way of doing it and there you were giving it a shot. And now following it up with this code sample which is just awesome. I really appreciate your your work.

Played around a little with Erlang and raring to explore ErlyWeb. :)