The best moment when you may appreciate this little gem is after re-installing the whole system and, provided that you did not forget to save all your essential data, iBackup is there to restore all these, including keychain (I bet you forgot how many sites require your login name and pasword) and various other sys hidden data.
Do not waste the capabilities for banal savings, e.g. your files, just copy them via drag-and-drop to a CD or flash-drive or another partition. use it for saving those hidden data you need so much.