TITLE: Broader impacts and synergistic activities
QUESTION [24 upvotes]: Since it was suggested on my last NSF proposal question, I thought I might also tap the collective brain on the question of broader impacts and synergistic activities.  These concepts are still slightly unclear to me, though I understand them a lot better than I did when I wrote this blog post (which actually resulted in some pretty good advice).  So let me ask:

What are some examples of synergistic activites and activities with "broader impacts" that many of us are doing, but haven't thought of to list in our NSF proposals?  What are some ones we probably should be doing, but maybe aren't?

I'm particularly interested in the answers for young mathematicians.  Most of the proposals I've read are from more senior people, who could point to their track record of mentoring graduate students and postdocs, or things like editing journals, in a way someone my age really can't.

REPLY [5 votes]: The Computer Science Directorate of NSF (CISE) held a
"Broader Impacts for Research and Discovery Summit" this past June. 
A summary of the meeting appeared in Computing Research News (p.6), including
this list of examples, only one of which is specific to computer science:

 Develop educational materials for elementary, high-school and undergraduate students.
 Involve high-school and undergraduate students in research where appropriate.
 Create or participate in existing effective mentoring programs. 
 Develop, maintain and operate a shared research infrastructure.
 Establish international, industrial or government collaborations.
 Form start-up companies. 
 Present research results to non-scientific audiences from policy-makers to average citizens. 
 Give presentations about the field to the public to foster life-long learning. 
 Develop exhibits in partnership with museums.