Aperture & libraries
You can export folder (in your example 2009) as a library. This self contained library can be stored where you like and once reattached it is very easy to switch libraries from within Aperture. The only shortcoming of this is that images from 2009 are only available when that library is open.
|Leaving the office, Central London. by Edward48|
from Your City - Night Shift
|Running free by LassiM|
from My Best Photo of the Week
|Everyone's happy at Disney World! by Pixney|
from Disney World