Should add a field to out

{ out :

}

tricky part is filling in "result" field.
I think best solution is having it start with a .
so normal would be "result" ; "foo"
with this would be ".other.foo"

OLD:
We have "rawdata" on a DB, and reduced collections on a different DB.

For us it could be interesting to do output='ReducedDB.NewReducedCollection

This would help moving a lot of data from one DB to another One.

Would be great in combination with this one:

http://jira.mongodb.org/browse/SERVER-647