I'm interested in the concept of web-based integrated development environments, IDEs. Basically, that means writing and testing code via a web browser, without a computer in the traditional sense. That's because I'm thinking more and more about a browser-only, workstation-less world. The only thing I still need a traditional computer for is programming. If that can be moved into the cloud, then I'm free!
Bespin looks like an excellent attempt to this end. The video is quite compelling. The main thing I would care about in such environment is the performance of typing and editing. The demonstrated zipping around, effortlessly, in a 33-k line file is impressive in the Bespin video.
I think I can't write and edit code without Emacs, but the truth is I spend a lot of my time typing into browser windows and text fields just like I am right now. A lot.
Google Documents' word processor is also a pretty good model for browser text editing. The text entry is interactive and fast. Document saves are automatic and there's version control. With line-number recognition, a monospaced font, keyword highlighting (which I've now sadly come to depend on), and even typing help such as auto-complete may not be too bad.
With a button to run tests, etc., the edit and test cycle could be pretty nice.
See also Part 2 and Part 3.