Sorry for all the posts, it took a while to catch up to this conversation
My perspective is that through your paid, career-path-following day job work you can help the world through design, in consultancies in particular.
-
focus on medical or social products that provide benefits for people (for example: diabetes products are huge with consultancies).
-
Find the causes yourself, define a problem, and build a business case around it for a firm/corp to spend the time - PR/Corporate Social Responsibility are good business cases that don’t require profits
-
do it on your own. Find a problem and a way to support yourself doing it. Doing good work, and promoting it when finished would be career building
-
Inject your social ethics into projects. Designers refuse to work on weapons, smoking products, or (sometimes) products they find objectionable. If there’s a problem, you have the option to leave as Yo said.
-
As a designer you can champion features for environmental or socially responsible reasons in products you work on
[/list]