"Here's a 'fake' bomb"
TSA gave it to you to plant to see if they could find it. Add some complexity to the test, don't make it easy and hide it in your carry on bag. The goal here is to TEST the screeners, right? Help them out. It will make them better. ^
If someone gives you something, it is a GIFT, right? So you can keep it. Go put it in your car, then come back and sail thru the checkpoint. While TSA Tester scratches his head and yells at the xray op for missing a bomb which does not exist. Then sell the fake bomb on ebay, I'm sure many FTers would love one for an office decoration artifact. Mailing it to Kip with a "Returning what belongs to you" note might not be the wisest idea.
Or drop it in a trash can which hopefully the cleaning crew will not find until after your flight leaves so you miss the fun of the terminal dump. Or is it a crime to throw Government Property into the trash after it was gifted to you?
"1001 Uses for a Gift Fake Bomb"
Look for it at the airport newsstand.