As touched on in the previous post, doing a lot of work with password policies at the minute.
Say you need to find the date all the members of a group last changed their password, below is all you need to do:
Get-QADGroupMember 'domainname\groupname' | Get-QADUser -IncludeAllProperties | ft displayname,pwdlastset
The pwdlastset parameter will (obviously) give you the time and date the password was last checked. It's pretty straightforward moving on from there to start doing things like finding which of these users' passwords will expire shortly.