Where are the web-based web-development IDEs?

[kf]

[davidw]

It's not a real IDE (it uses an unenhanced textarea), but I whipped up this as a demo of Hecl. Basically, you can write Hecl scripts on a web page and then download a fully formed mobile application:

http://builder.hecl.org

[kf]

I don't think there are any web based IDEs for python/Ruby or even HTML/CSS. Is there a technical reason these don't exist or that desktop IDEs are preferable?

[bootload → kf]

borland, sorry Codegear has delphi for php ~ http://www.codegear.com/products/delphi/php

[jey → kf]

What's the benefit of such a thing?

[kf → jey]

It could be a more intuitive way of collaborating.