Scratch

You can do a screen capture of your Scratch project just like from any other application. If you are on Windows, I would recommend Camtasia. It exports into Flash and several video formats.

I assume you are aware that Scratch is more than just animations. A lot of people use input from mouse or keyboard, or other sources of input which cannot be captured on a video. I would be curious to know what you do with Scratch.

Thanks for Scratching! 

This feature could be provided with a lot less memory than a full video recording by providing a "journal" feature that records every interaction with a timestamp. Perhaps each broadcast and move would need to be recorded with a timestamp also.  It would also have to record every number that comes out of the random number generator each time it is called, so that exactly the same sequence can be repeated.

Playing back the journal should repeat the same movie (as long as the playback machine was fast enough---you may not be able to duplicate the actions of a fast machine on a slow one).

Of course, there *is* a lot of demand for animated movie clips, so having an easy way to record the action on the scratch screen as a movie would be a nice feature, though I expect that squeak is not fast enough for that to be feasible.

Control by keyboard could be a problem, as you may not have "chord" control---most keyboard interfaces will only report one key down at a time (other than shift and control keys, which scratch provides no access to).  Auto-repeat keys can also mess up the semantics of the key interface.

It would be nice if the scratch documentation was clearer about how the program implementation handles keyboard interfaces.