We need to add documentation for the new "dynamicComponents" option. A placeholder has been added to
http://wiki.fluidproject.org/display/docs/Component+Configuration+Options
but the details are not yet there, and we should probably discuss them in a bit more detail elsewhere, perhaps here?
http://wiki.fluidproject.org/display/docs/Subcomponent+Declaration

My notes on dynamic components so far:

can do different things:
a) create multiple copies of a component given a "sources" array (or object)
b) create a component on an event, but only on the first event (normally, createOnEvent will create on every firing)

Tests exist for a) above, but not for b). Yura says Kettle uses them, so there may be some examples there.