Google Apps has a really cool feature that allows you to send an email from any alias assigned to your account or any group list that you belong to. For example, sometimes I want to send an email as "TeamSCHift@SCH.org" or "Tech@SCH.org", mail group lists not my individual GApps "pdidonato@SCH.org" account. To send an email as an alias or group address, follow these directions.
Hope this helps
--Pete