I will make sure you have extra time to work on your reports or presentations.
Simply send me the file and I will corrupt the sent file.
Your teacher or boss wil think you delivered on time but won't be able to open it due to techonology hassle, giving you more time to finish the actual report or presentation!
Nope! You will still have the original file you're working on and will be given the corrupted file to hand in with the same filename and size.