What application can I use for cropping quickly (selecting multiple areas of an image)?

Looks like you may find a solution on the Ubuntu forums here; http://ubuntuforums.org/showthread.php?t=1429439 download the python script install the pre requisites,

sudo apt-get install python-tk python-imaging python-imaging-tk 

run the application, load file, select areas to crop with mouse and click go, pictures of the areas will be saved to file in the folder with the photo. see below:

View of files in nautilus