We need to know the age of users and their children to invite them to take demo-graphically targeted actions on our site.
Privacy concerns are being raised around getting that specific information, and we're thinking of going with Month/Year instead of asking for a full DOB.
I'm suggesting we go with a dual drop-down interface showing months (January, February, etc.), and years (1993, 1992, etc., (users have to be at least 18, so starting there).