This will add the following:
unknown sources hack
ez file explorer
Home Manager (allows you to switch between launchers easily)
NT Hidden Setting
Amazon App Store
Slashtop HD (Free from getjar)
Flash the image to an SDCard greater than 2GB
Power Down Nook
Put in sdcard
Choose "Apply update.zip from sdcard"
When it is finish, remove sdcard and choose reboot.
Thanks quid246 for pointing out an issue with the permissions.
Download image file:
Download imaging software