Second additional backend password

How about a second additional backend password which can be activated and de-activated when necessary.

Don't you often post a topic at a forum and the developer asks you for backend access? Everytime you give backend administrator access you need to change that password again once the developer doesn't need backend access anymore. You don't want him to have infinite backend access.

If you have a second additional backend password you can simply activate it when a developer needs backend access and you can keep using your own one.