Sittercity: This is free to us so long as you are military. I think this is only for Active duty members, but don't know since I didn't know about Sittercity until we were active duty.
SeaWorld, Busch Gardens, and Sesame Place: Throughout 2011 they are allowing military members and 3 dependents (with ID's) in for free. There is more to it, so you will want to read the fine print.
Hero Care: These guys are new and are still trying to go nation wide, but where they are, they are VERY helpful.